tag:theconversation.com,2011:/au/topics/eggs-4254/articlesEggs – The Conversation2024-03-11T21:26:04Ztag:theconversation.com,2011:article/2217202024-03-11T21:26:04Z2024-03-11T21:26:04ZAllergen warning: “Vegan” foods may contain milk and eggs<figure><img src="https://images.theconversation.com/files/570731/original/file-20240112-29-t9z77z.jpg?ixlib=rb-1.1.0&rect=4%2C0%2C989%2C667&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">When buying pre-packaged foods, consumers with allergies rely on the declarations in the list of ingredients to identify safe foods.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>The popularity of vegan diets continues to increase around the world. Indeed, in 2023, the vegan food market grew to <a href="https://www.expertmarketresearch.com/reports/vegan-food-market">more than US$27 billion</a>.</p>
<p>The term “vegan” usually refers to foods that contain no animal ingredients (meat, poultry, eggs, milk, fish, seafood).</p>
<p>While some consumers consider them to be healthier, vegan foods are also an interesting alternative for consumers concerned about the environment, sustainable development, and animal welfare.</p>
<p>But another type of consumer may be turning to these products for a completely different reason: people who are allergic to proteins of animal origin, such as cow’s milk and eggs.</p>
<p>In view of this, <a href="https://parera.ulaval.ca">our research group</a>, a leader in food allergen risk analysis in Canada, decided to explore <a href="https://link.springer.com/article/10.1186/s13223-023-00836-w">the following two questions</a>:</p>
<ul>
<li><p>Do consumers who are allergic to animal proteins consider vegan products to be safe?</p></li>
<li><p>And, if so, are these products truly safe for them?</p></li>
</ul>
<h2>What’s in it for consumers with allergies?</h2>
<p>The answers to these questions are crucial for people with food allergies who risk suffering potentially severe reactions (anaphylaxis) from consuming these products.</p>
<p>Food allergies affect around <a href="https://www.jaci-inpractice.org/article/S2213-2198(19)30912-2/fulltext">six per cent of Canadians</a>, including 0.8 per cent who are allergic to eggs, and 1.1 per cent to milk.</p>
<p>Despite the fact that different forms <a href="https://foodallergycanada.ca/living-with-allergies/allergy-treatments-and-therapies/treatments-and-therapies/">of immunotherapy or allergen desensitization</a> have shown promising results, the most effective strategy for avoiding allergic reactions is still to refrain from eating foods that may contain allergens.</p>
<p>When buying pre-packaged foods, consumers with allergies rely on declarations in the list of ingredients to identify foods that are safe for them. Regulatory authorities who are responsible for the quality and safety of food recognize the importance of accurate ingredients declarations for allergic consumers. Thus, it is <a href="https://www.canada.ca/en/health-canada/services/food-nutrition/food-labelling/allergen-labelling.html">mandatory</a> to list every allergen that has been voluntarily added to a pre-packaged food item.</p>
<p>However, when it comes to ingredients that may be unintentionally present — for example, as due to cross-contact during food processing — there is a regulatory gap. These ingredients are generally identified with the warning “may contain,” which is used (or sometimes <a href="https://www.sciencedirect.com/science/article/abs/pii/S2213219818300102">overused</a>) voluntarily and randomly by food processors.</p>
<p>Furthermore, the term “vegan” is neither standardized nor defined in Canadian regulations. In fact, <a href="https://inspection.canada.ca/food-labels/labelling/industry/composition-and-quality/eng/1625516122300/1625516122800?chap=2">the Canadian Food Inspection Agency</a> notes that, with regard to the use of the term “vegan,”</p>
<blockquote>
<p>…companies can apply additional criteria or standards that take account of other factors in addition to the ingredients of the food.</p>
</blockquote>
<p>However, details or examples of these elements are not provided. This lack of a precise regulatory definition prevents the implementation of compliance requirements.</p>
<p>Yet, most <a href="https://recalls-rappels.canada.ca/en/search/site?search_api_fulltext=vegan">recalls</a> of products marketed as “vegan” are due to the presence of undeclared ingredients of animal origin, in particular milk and eggs.</p>
<h2>What do consumers with food allergies say?</h2>
<p>In this context, and as part of a <a href="https://www.researchsquare.com/article/rs-2583779/v1">survey</a> of consumers with allergies conducted in collaboration with <a href="https://foodallergycanada.ca">Food Allergy Canada</a>, we asked participants who indicated that they were allergic (or were the parents of a child who was allergic) to eggs or milk if they bought products marketed as “vegan.”</p>
<p>Of the 337 respondents, 72 per cent said they sometimes included these products in their purchases, 14 per cent said they always did, and 14 per cent never.</p>
<p>These <a href="https://link.springer.com/article/10.1186/s13223-023-00836-w">results</a> suggest that these consumers do, indeed, consider the claim “vegan” as an indicator of the absence of animal proteins — an absence which, again, is not supported by any regulatory requirement or definition.</p>
<p>Since the absence of these ingredients is not guaranteed, these consumption habits could put people who are allergic to eggs and/or milk at risk.</p>
<p>An education campaign to clarify that the term “vegan” is an indicator of dietary <em>preferences</em> and not <em>risks</em> would therefore be important for this community.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="dark chocolate" src="https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=372&fit=crop&dpr=1 600w, https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=372&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=372&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=467&fit=crop&dpr=1 754w, https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=467&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/569134/original/file-20240112-29-5nq5bg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=467&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Some dark chocolate bars marketed as ‘certified vegan’ contain milk proteins.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>Do vegan products contain ingredients of animal origin?</h2>
<p>The fact that 86 per cent of survey respondents buy “vegan” products suggests that the incidence of allergic reactions linked to these foods is potentially rare.</p>
<p>We therefore <a href="https://link.springer.com/article/10.1186/s13223-023-00836-w">analyzed</a> the egg and milk protein content of “vegan” and “plant-based” products marketed in Québec.</p>
<p>A total of 124 products were analyzed for the presence of egg (64) and/or milk (87) proteins.</p>
<p>Egg protein was not detected in any samples, but five samples contained milk proteins: these included four dark chocolate bars marketed as “certified vegan” and a supermarket brand chestnut cake.</p>
<p>These five products declared the potential presence of milk with a warning, “may contain milk.”</p>
<p>We used the concentrations of milk proteins quantified in these products, combined with the quantities of the food that would be consumed in a single eating occasion, to calculate an exposure dose, in milligrams of allergen protein. We then estimated the probability of these doses provoking a reaction in the allergic populations concerned by using <a href="https://www.sciencedirect.com/science/article/pii/S0278691520307213">correlation models</a>. Our results show that the calculated doses could trigger reactions in six per cent of milk-allergic consumers, for the chocolate bars, and one per cent, for the cake.</p>
<h2>How can consumers with food allergies protect themselves?</h2>
<p>Although this level of risk may be perceived as low, it is likely to vary without notice. And this will remain the case until regulatory requirements are put in place.</p>
<p>In fact, rather than attributing it to the presence of a “vegan” or “plant-based” claim, this level of risk most likely reflects <a href="https://www.cell.com/heliyon/pdf/S2405-8440(22)02590-7.pdf">good allergen management practices</a>, characteristic of the North American food manufacturing sector.</p>
<p>Thus, even if a statement “may contain milk” seems contradictory in a “vegan” or “plant-based” product, people allergic to milk should interpret it as an indication that this product may pose a risk to their health.</p><img src="https://counter.theconversation.com/content/221720/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Samuel Godefroy's research activities are funded by the Natural Sciences and Engineering Research Council of Canada, the Foreign Agriculture Service of the United States Department of Agriculture, R-Biopharm GmbH and R-Biopharm Canada Inc. He acts as an expert advisor to members of the food and beverage industry, international organizations (the Food and Agriculture Organization of the United Nations, the United Nations Industrial Development Organization and the World Bank), international food regulatory bodies such as the China National Centre for Food Safety Risk Assessment and consumer organizations such as Food Allergy Canada. Godefroy is Chairman of the Board of the Global Food Regulatory Science Society (GFoRSS).</span></em></p><p class="fine-print"><em><span>Jérémie Théolier et Silvia Dominguez ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'ont déclaré aucune autre affiliation que leur poste universitaire.</span></em></p>Vegan foods are considered by most consumers to have no ingredients of animal origin, but they may actually contain milk proteins.Silvia Dominguez, Professionnelle de recherche en sciences des aliments, Université LavalJérémie Théolier, Professionel de recherche en sciences des aliments, Université LavalSamuel Godefroy, Professeur titulaire - Sciences des aliments, Université LavalLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2197152024-02-22T14:37:56Z2024-02-22T14:37:56ZKalahari weaver birds lay bigger eggs when they have female helpers to feed nestlings<p><a href="https://tswalu.com/">Tswalu Kalahari Reserve</a> is a protected nature reserve at the southern edge of the Kalahari desert in South Africa’s Northern Cape province. It’s an arid area with high daytime temperatures and <a href="https://www.science.org/doi/10.1126/sciadv.abe8980">unpredictable rainfall</a>.</p>
<p>One of the species that lives in this harsh environment is the <a href="https://ebird.org/species/wbswea1?siteLanguage=en_ZA">white-browed sparrow-weaver</a> (<em>Plocepasser mahali</em>). They live here in social groups of up to 12 birds. Group members stay in the same group for many years at a time. </p>
<p>Within each social group, only one pair of birds breeds: the dominant male and female (which lays one to three eggs per breeding attempt). Other group members – usually offspring of the breeding pair – engage in a number of helping behaviours, from defending the territory to feeding the nestlings of the dominant pair.</p>
<p>This is not the only species in which the breeding pair has help raising the young. <a href="https://science.uct.ac.za/fitzpatrick/research-understanding-biodiversity-evolutionary-and-behavioural-ecology/pied-babblers-and-fork-tailed-drongos">Southern pied babblers</a> and <a href="https://theconversation.com/biggest-bird-nests-in-the-world-are-kept-together-by-family-ties-28932">sociable weavers</a> are other examples in the Kalahari. This type of behaviour, known as cooperative breeding, occurs globally and seems to be particularly associated with arid habitats. However, it’s still not clear what benefits it offers and how it aids species to adapt to the environment.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/birds-evolve-different-body-temperatures-in-different-climates-new-study-of-53-african-species-189174">Birds evolve different body temperatures in different climates – new study of 53 African species</a>
</strong>
</em>
</p>
<hr>
<p>In a long-term <a href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3002356#sec007">study</a> recently published in the journal PLOS Biology, covering 10 years of research (from 2007 to 2016) at the Tswalu Kalahari Reserve, my University of Exeter research colleagues and I added some evidence to help answer this question. Our study revealed that white-browed sparrow-weaver mothers lay larger eggs when they have help with nestling care. Egg size is an important trait which affects nestling survival. </p>
<p>This is the first formal evidence in birds that maternal investment in eggs changes with the availability of help. The results also counter the idea previously proposed that with more help, mothers would lay smaller eggs.</p>
<h2>Understanding correlations</h2>
<p><a href="https://peerj.com/articles/4028/">Previous studies</a> of cooperatively breeding birds have tended to find a correlation between having more helpers and laying smaller eggs. However, it was unclear whether this correlation arose from mothers changing their egg size according to the social conditions they experienced (known as “<a href="https://royalsocietypublishing.org/doi/10.1098/rstb.2009.0267">plasticity</a>”), or if other confounding factors could be explaining the results.</p>
<p>By using a number of statistical tools, we could investigate whether individual white-browed sparrow-weaver mothers laid larger or smaller eggs depending on their social conditions. The number of helpers during the post-natal phase is strongly correlated with the number of helpers when mothers laid eggs. So mothers should have reliable information to adjust egg size based on the availability of help with post-natal care. We found that mothers laid larger eggs in the presence of (female) helpers and they also reduced their feeding rates to the offspring.</p>
<p>In white-browed sparrow-weavers, <a href="https://www.science.org/doi/10.1126/sciadv.abe8980">female helpers provide significantly more post-natal care than male helpers</a>. The fact that the number of female helpers (and not male helpers) positively predicted egg size suggests the availability of cooperative care (and not simply the presence of helpers) as the causal mechanism of our results.</p>
<p>These findings indicate it is possible that having help allows mothers to invest more into pre-natal (egg) development of her offspring, to which helpers cannot contribute directly.</p>
<h2>Helpers and benefits to offspring</h2>
<p>It is possible that the lightening of maternal post-natal investment (feeding of nestlings) allows the mother bird to invest more resources into bigger eggs, which are then more likely to hatch into nestlings that survive into adulthood. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/female-warblers-live-longer-when-they-have-help-raising-offspring-115332">Female warblers live longer when they have help raising offspring</a>
</strong>
</em>
</p>
<hr>
<p>Through positive helper effects on pre-natal maternal investment, helper assistance with the post-natal care of breeders’ young in cooperative species (including our own) may thus have hitherto unknown benefits to offspring.</p><img src="https://counter.theconversation.com/content/219715/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pablo Capilla-Lasheras has received funding from the Biotechnology and Biological Sciences Research Council (UK) and currently works at the University of Glasgow.</span></em></p>The study shows that bird mothers can adjust egg size depending on their social conditions. This counters the idea that, with more help, mothers lay smaller eggs.Pablo Capilla-Lasheras, Research Associate in ecology, evolution and behaviour, University of GlasgowLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2020362024-02-19T00:42:34Z2024-02-19T00:42:34ZRun out of butter or eggs? Here’s the science behind substitute ingredients<figure><img src="https://images.theconversation.com/files/575492/original/file-20240213-28-yaukh5.jpg?ixlib=rb-1.1.0&rect=80%2C35%2C5784%2C3952&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/white-soup-on-brown-ceramic-bowl-wg5kaMtJ3Ts">Joanna Lopez/Unsplash</a></span></figcaption></figure><p>It’s an all too common situation – you’re busy cooking or baking to a recipe when you open the cupboard and suddenly realise you are missing an ingredient.</p>
<p>Unless you can immediately run to the shops, this can leave you scrambling for a substitute that can perform a similar function. Thankfully, such substitutes can be more successful than you’d expect.</p>
<p>There are a few reasons why certain ingredient substitutions work so well. This is usually to do with the chemistry and the physical features having enough similarity to the original ingredient to still do the job appropriately. </p>
<p>Let’s delve into some common ingredient substitutions and why they work – or need to be tweaked.</p>
<p><iframe id="IitfH" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/IitfH/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>Oils versus butter</h2>
<p>Both butter and oils belong to a chemical class called <a href="https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Map%3A_Fundamentals_of_General_Organic_and_Biological_Chemistry_(McMurry_et_al.)/23%3A_Lipids/23.01%3A_Structure_and_Classification_of_Lipids">lipids</a>. It encompasses solid, semi-solid and liquid fats.</p>
<p>In a baked product the “job” of these ingredients is to provide flavour and influence the structure and texture of the finished item. In cake batters, lipids contribute to creating an emulsion structure – this means combining two liquids that wouldn’t usually mix. In the baking process, this helps to create a light, fluffy crumb.</p>
<p>One of the primary differences between butter and oil is that butter is only about 80% lipid (the rest being water), while <a href="https://www.nutritionadvance.com/types-of-cooking-fats-and-oils/">oil is almost 100% lipid</a>. Oil creates a softer crumb but is still a great fat to bake with.</p>
<p>You can use a wide range of oils from different sources, such as olive oil, rice bran, avocado, peanut, coconut, macadamia and many more. Each of these may impart different flavours.</p>
<p>Other “butters”, such as peanut and cashew butter, aren’t strictly butters but pastes. They impart different characteristics and can’t easily replace dairy butter, unless you also add extra oil.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A block of yellow butter in an open silver foil wrapper" src="https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=491&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=491&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575161/original/file-20240213-30-j0czv9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=491&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Nut ‘butters’ can’t replace dairy butter because their composition is too different.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/butter-good-butter-fat-nourishment-3411126/">congerdesign/Pixabay</a></span>
</figcaption>
</figure>
<h2>Aquafaba or flaxseed versus eggs</h2>
<p>Aquafaba is the liquid you drain from a can of legumes – such as chickpeas or lentils. It contains proteins, kind of how egg white also contains proteins.</p>
<p>The proteins in egg white include albumins, and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5912395/">aquafaba also contains albumins</a>. This is why it is possible to make meringue from egg whites, or from aquafaba if you’re after a vegan version.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-make-the-perfect-pavlova-according-to-chemistry-experts-196485">How to make the perfect pavlova, according to chemistry experts</a>
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</em>
</p>
<hr>
<p>The proteins act as a foam stabiliser – they hold the light, airy texture in the product. The concentration of protein in egg white is a bit higher, so it doesn’t take long to create a stable foam. Aquafaba requires more whipping to create a meringue-like foam, but it will bake in a similar way. </p>
<p>Another albumin-containing alternative for eggs is <a href="https://foodstruct.com/compare/seeds-flaxseed-vs-egg">flaxseed</a>. These seeds form a thick gel texture when mixed with a little water. The texture is similar to raw egg and can provide structure and emulsification in baked recipes that call for a small amount of egg white. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/eggs-are-so-expensive-right-now-what-else-can-i-use-207837">Eggs are so expensive right now. What else can I use?</a>
</strong>
</em>
</p>
<hr>
<h2>Lemon plus dairy versus buttermilk</h2>
<p>Buttermilk is the liquid left over after churning butter – it can be made from sweet cream, cultured/sour cream or whey-based cream. Buttermilk mostly <a href="https://www.journalofdairyscience.org/article/S0022-0302(06)72115-4/fulltext">contains proteins and fats</a>.</p>
<p>Cultured buttermilk has a somewhat tangy flavour. Slightly soured milk can be a good substitute as it contains similar components and isn’t too different from “real” buttermilk, chemically speaking.</p>
<p>One way to achieve slightly soured milk is by adding some lemon juice or cream of tartar to milk. Buttermilk is used in pancakes and baked goods to give extra height or volume. This is because the acidic (sour) components of buttermilk interact with baking soda, producing a light and airy texture. </p>
<p>Buttermilk can also influence flavour, imparting a slightly tangy taste to pancakes and baked goods. It can also be used in sauces and dressings if you’re looking for a lightly acidic touch. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A stack of fluffy pancakes dusted with sugar with a strawberry on top" src="https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575163/original/file-20240213-16-ol6va7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Buttermilk is a common ingredient for making fluffy pancakes.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/pancakes-food-strawberry-plate-2801959/">Matthias_Groeneveld/Pixabay</a></span>
</figcaption>
</figure>
<h2>Honey versus sugar</h2>
<p>Honey is a <a href="https://resources.perkinelmer.com/lab-solutions/resources/docs/APP_Analysis-of-Sugars-in-Honey-012101_01.pdf">complex sugar-based syrup</a> that includes floral or botanical flavours and aromas. Honey can be used in cooking and baking, adding both flavour and texture (viscosity, softness) to a wide range of products.</p>
<p>If you add honey instead of regular sugar in baked goods, keep in mind that honey imparts a softer, moister texture. This is because it contains more moisture and is a humectant (that is, it likes to hold on to water). It is also less crystalline than sugar, unless you leave it to crystallise.</p>
<p>The intensity of sweetness can also be different – some people find honey is sweeter than its granular counterpart, so you will want to adjust your recipes accordingly.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Close-up of a slice of bread with golden honey pooling on top" src="https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/575164/original/file-20240213-26-6c2r7t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Honey has a complex flavour and can taste sweeter than regular sugar.</span>
<span class="attribution"><a class="source" href="https://pixabay.com/photos/honey-bread-spoon-bio-nature-752145/">estelheitz/Pixabay</a></span>
</figcaption>
</figure>
<h2>Gluten-free versus regular flour</h2>
<p>Sometimes you need to make substitutions to avoid allergens, such as gluten – the protein found in cereal grains such as wheat, rye, barley and others. </p>
<p>Unfortunately, gluten is also the component that gives a nice, stretchy, squishy quality to bread.</p>
<p>To build this characteristic in a gluten-free product, it’s necessary to have a mixture of ingredients that work together to mimic this texture. Common ingredients used are corn or rice flour, xanthan gum, which acts as a binder and moisture holder, and tapioca starch, which is a good water absorbent and can aid with binding the dough. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/thank-glutens-complex-chemistry-for-your-light-fluffy-baked-goods-216869">Thank gluten's complex chemistry for your light, fluffy baked goods</a>
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</em>
</p>
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<img src="https://counter.theconversation.com/content/202036/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Paulomi (Polly) Burey does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>In a pinch, the water from a can of beans can replace eggs. But how does that work, exactly?Paulomi (Polly) Burey, Associate Professor (Food Science), University of Southern QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2190052023-12-14T19:19:48Z2023-12-14T19:19:48ZEggs from men, sperm from women: how stem cell science may change how we reproduce<figure><img src="https://images.theconversation.com/files/564442/original/file-20231208-17-22yb4u.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1000%2C748&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-illustration/morula-early-stage-embryo-consisting-cells-776035219">nobeastsofierce/Shutterstock</a></span></figcaption></figure><p>It may soon be possible to coax human skin cells into becoming functional eggs and sperm using a technique known as “in vitro gametogenesis”. This involves the creation (genesis) of eggs and sperm (gametes) outside the human body (in vitro). </p>
<p>In theory, a skin cell from a man could be turned into an egg and a skin cell from a woman can become a sperm. Then there’s the possibility of a child having multiple genetically-related parents, or only one.</p>
<p>Some scientists believe human applications of in vitro gametogenesis are a <a href="https://www.statnews.com/2023/10/02/ivg-ivf-replacement-reproductive-technology-hype/">long way off</a>. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1708819232077533218"}"></div></p>
<p>However, scientists who work on human stem cells are <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10579208/">actively working</a> on overcoming the barriers. <a href="https://www.statnews.com/2023/04/08/ivf-eggs-hormones-gameto-reproductive-fertilo/">New</a> <a href="https://www.technologyreview.com/2021/10/28/1038172/conception-eggs-reproduction-vitro-gametogenesis/">biotechnology</a> <a href="https://www.newyorker.com/magazine/2023/04/24/the-future-of-fertility">start-ups</a> are also seeking to commercialise this technology.</p>
<p>Here’s what we know about the prospect of human in vitro gametogenesis and why we need to start talking about this now.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-what-are-stem-cells-14391">Explainer: what are stem cells?</a>
</strong>
</em>
</p>
<hr>
<h2>Is the technology available?</h2>
<p>In vitro gametogenesis begins with “pluripotent stem cells”, a kind of cell that can develop into many different cell types. The aim is to persuade these stem cells to become eggs or sperm.</p>
<p>These techniques could use stem cells taken from early embryos. But scientists have also worked out how to <a href="https://www.eurostemcell.org/stemcellshorts-what-are-induced-pluripotent-stem-cells">revert adult cells</a> to a pluripotent state. This opens up the possibility of creating eggs or sperm that “belong to” an existing human adult.</p>
<p>Animal studies have been promising. In <a href="https://www.nature.com/articles/490146b">2012</a>, scientists created live-born baby mice using eggs that began their life as skin cells on a mouse tail.</p>
<p>More recently, the technique has been used to facilitate same-sex reproduction. Earlier this year, scientists created mouse pups with <a href="https://www.nature.com/articles/d41586-023-00717-7">two genetic fathers</a> after transforming skin cells from male mice into eggs. Mouse pups with <a href="https://www.nature.com/articles/d41586-018-06999-6">two genetic mothers</a> have also been created.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/1ocWjHJgKcc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How scientists bred mice with two fathers.</span></figcaption>
</figure>
<p>Scientists have not yet managed to adapt these techniques to create human gametes. Perhaps because the technology is still in its infancy, Australia’s legal and regulatory systems do not address whether and how the technology should be used. </p>
<p>For example, the National Health and Medical Research Council’s <a href="https://www.nhmrc.gov.au/about-us/publications/art">assisted reproduction guidelines</a>, which were updated in 2023, do not include specific guidance for in vitro-derived gametes. These guidelines will need to be updated if in vitro gametogenesis becomes viable in humans.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-future-of-stem-cells-tackling-hype-versus-hope-72052">The future of stem cells: tackling hype versus hope</a>
</strong>
</em>
</p>
<hr>
<h2>The potential</h2>
<p>There are three distinct clinical applications of this technology.</p>
<p>First, in vitro gametogenesis could streamline IVF. Egg retrieval currently involves repeated hormone injections, a minor surgical procedure, and the <a href="https://www.mayoclinic.org/diseases-conditions/ovarian-hyperstimulation-syndrome-ohss/symptoms-causes/syc-20354697">risk</a> of overstimulating the ovaries. In vitro gametogenesis could eliminate these problems.</p>
<p>Second, the technology could circumvent some forms of medical infertility. For example, it could be used to generate eggs for women born without functioning ovaries or following early menopause.</p>
<p>Third, the technology could allow same-sex couples to have children who are genetically related to both parents.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/promising-assisted-reproductive-technologies-come-with-ethical-legal-and-social-challenges-a-developmental-biologist-and-a-bioethicist-discuss-ivf-abortion-and-the-mice-with-two-dads-208276">Promising assisted reproductive technologies come with ethical, legal and social challenges – a developmental biologist and a bioethicist discuss IVF, abortion and the mice with two dads</a>
</strong>
</em>
</p>
<hr>
<h2>Legal, regulatory and ethical issues</h2>
<p>If the technology becomes viable, in vitro gametogenesis will alter the dynamics of how we create families in unprecedented ways. How we should respond requires careful consideration.</p>
<p><strong>1. Is it safe?</strong></p>
<p>Careful trials, rigorous monitoring, and follow-up of any children born will be essential – as it has been for other <a href="https://theconversation.com/maeves-law-would-let-ivf-parents-access-technology-to-prevent-mitochondrial-disease-heres-what-the-senate-is-debating-176668">reproductive</a> <a href="https://theconversation.com/rest-assured-ivf-babies-grow-into-healthy-adults-23432">technologies</a>, including IVF.</p>
<p><strong>2. Is it equitable?</strong></p>
<p>Other issues relate to access. It might seem unjust if the technology is only available to the wealthy. Public funding could help – but whether this is appropriate depends on whether the state <a href="https://theconversation.com/ideas-for-australia-rethinking-funding-and-priorities-in-ivf-should-the-state-pay-for-people-to-have-babies-57036">ought to support</a> people’s reproductive projects.</p>
<p><strong>3. Should we restrict access?</strong></p>
<p>For instance, pregnancy is rare in older women, largely because egg count and quality <a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/age-and-fertility">decline with age</a>. In vitro gametogenesis would theoretically provide “fresh” eggs for women of any age. But helping older women become parents is <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5566409/">controversial</a>, due to physical, psychological and other factors associated with having babies later in life.</p>
<p><strong>4. We’d still need surrogates</strong></p>
<p>If we took skin cells from each male partner and created an embryo, that embryo would still need a surrogate to carry the pregnancy. Unfortunately, Australia has a shortfall of surrogates. International surrogacy provides an alternative, but carries <a href="https://theconversation.com/its-hard-to-find-a-surrogate-in-australia-but-heading-overseas-comes-with-risks-206182">legal, ethical and practical difficulties</a>. Unless access to surrogacy is improved domestically, benefits to male couples will be limited. </p>
<p><strong>5. Who are the legal parents?</strong></p>
<p>In vitro gametogenesis also raises questions about who are the future child’s legal parents. We already see related legal debates surrounding non-traditional families formed through surrogacy, egg donation and sperm donation. </p>
<p>In vitro gametogenesis could theoretically also be used to create children with more than two genetic parents, or with only one. These possibilities likewise require us to update our current understandings of parenthood.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/we-may-one-day-grow-babies-outside-the-womb-but-there-are-many-things-to-consider-first-125709">We may one day grow babies outside the womb, but there are many things to consider first</a>
</strong>
</em>
</p>
<hr>
<h2>How far is too far?</h2>
<p>Of the potential uses already mentioned, same-sex reproduction is the most controversial. The reproductive limitations imposed by being in a same-sex relationship are sometimes seen as a “social” form of infertility the medical profession is not obligated to fix.</p>
<p>The moral stakes, however, are virtually identical regardless of whether in vitro gametogenesis is used by same-sex or opposite-sex couples. Both uses of the technology fulfil exactly the same goal: helping couples fulfil their desire to have a child genetically related to both parents. It would be unjust to deny access to only one of these groups.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Same-sex female couple cooking in kitchen, one feeding the other fruit" src="https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/564457/original/file-20231208-21-83z5z9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Who should have access to this technology? How about same-sex couples?</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/lesbian-couple-cooking-kitchen-together-1071305168">Rawpixel.com/Shutterstock</a></span>
</figcaption>
</figure>
<p>But same-sex reproduction is only the tip of the iceberg. In vitro gametogenesis could theoretically facilitate “<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6973109/">solo reproduction</a>” by deriving both eggs and sperm from the same individual. Interestingly, a child created this way would not be a clone of its parent, since the process of gamete formation would shuffle the parent’s genetic material and create a genetically distinct individual.</p>
<p>Or people could engage in “<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4215291/">multiplex parenting</a>” combining genetic material from more than two individuals. Imagine, for example, that two couples create embryos via IVF. In vitro gametogenesis could then be used to derive eggs and sperm from each of these two separate embryos, which could subsequently be used to conceive a single child that is genetically related to all four adults.</p>
<p>Finally, in vitro gametogenesis could revolutionise prenatal genetic selection. We’d have <a href="https://rmanetwork.com/blog/number-of-eggs-good-ivf-in-vitro-fertilization/">many more embryos</a> than available during regular IVF to screen for genetic diseases and traits.</p>
<p>So it would be urgent to discuss “designer babies”, eugenics, and whether we have a <a href="https://bioedge.org/bioethics-d75/savulescu-interviewed-on-procreative-beneficence/">moral obligation</a> to conceive children with the best chance of a good life.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/worlds-first-synthetic-embryo-why-this-research-is-more-important-than-you-think-188217">World's first 'synthetic embryo': why this research is more important than you think</a>
</strong>
</em>
</p>
<hr>
<h2>We need to start talking about this now</h2>
<p>Both law and ethics can lag behind new technologies, particularly when their implications are as profound and far-reaching as the implications of in vitro gametogenesis.</p>
<p>We need to discuss how this technology should be regulated before it is rolled out. Given how rapidly the science is developing, we should begin this discussion now. </p>
<hr>
<p><em>Laura Smith, a masters student from Monash University, contributed to this article.</em></p><img src="https://counter.theconversation.com/content/219005/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Julian Koplin receives research funding from Ferring Pharmaceuticals for an unrelated project.</span></em></p><p class="fine-print"><em><span>Neera Bhatia receives funding from UKRI Arts and Humanities Research Council for an unrelated project.</span></em></p>The technology may be here sooner than we think. But we have so much to discuss first.Julian Koplin, Lecturer in Bioethics, Monash University & Honorary fellow, Melbourne Law School, Monash UniversityNeera Bhatia, Associate Professor in Law, Deakin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2140562023-10-25T17:53:55Z2023-10-25T17:53:55ZIn defence of Bill C-282: Canada’s supply management supports farmers while safeguarding consumers<iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/in-defence-of-bill-c-282-canadas-supply-management-supports-farmers-while-safeguarding-consumers" width="100%" height="400"></iframe>
<p>The recent passage of <a href="https://www.parl.ca/DocumentViewer/en/44-1/bill/C-282/third-reading">Bill C-282</a>, legislation that prevents Canadian trade negotiators from surrendering additional supply managed commodities — like eggs and dairy — in international trade negotiations, has reignited debates over Canada’s supply management system.</p>
<p>Canada’s supply management system is designed to align the production of dairy, eggs and poultry with domestic consumption through the judicious use of quotas and tariffs. </p>
<p>Critics of the bill <a href="https://nationalpost.com/opinion/no-party-wants-to-kill-this-bill-that-could-keep-groceries-more-expensive-forever">argue it may hamstring our trade negotiators and raise food prices</a>, claiming that Canada’s supply management system is designed to “constrain supply, strangle competition with tariffs and keep prices high” by limiting dairy, eggs and poultry imports from the United States.</p>
<p>However, there is no evidence to support these claims. This kind of criticism relies on outdated beliefs in the sanctity of the so-called free market and its ability to produce cheap goods.</p>
<p>If Canada wishes to preserve domestic farms and enhance food security, officials must have limits on what they can give up to American and other foreign interests. We argue the current supply management model works to provide competitive prices to consumers, while also providing a living wage for farmers.</p>
<h2>The Canadian model is working</h2>
<p>If the COVID-19 pandemic has demonstrated anything over the past several years, it’s that <a href="https://www.uc.utoronto.ca/eating-age-covid-19-food-security-canada-during-and-after-pandemic">local food production is necessary to ensure food security</a>. Evidence suggests that the global food system has <a href="https://doi.org/10.1080/03066150.2022.2129013">exacerbated environmental degradation and food insecurity</a> while consolidating power in the hands of a select few global food corporations.</p>
<p>It’s clear we need to invest in local, community-based food sources — something supply management is able to facilitate by the nature of its operation. The supply management model is focused on supplying food to the Canadian market, with very limited opportunity for exports. </p>
<p>Under this model, dairy and eggs are generally marketed in the region in which they are produced — <a href="https://grayridge.com/">Ontario eggs are sold</a> in Ontario supermarkets — thereby privileging the local.</p>
<p>Supply management also <a href="https://www.nfu.ca/campaigns/food-sovereignty/">reflects some of the concepts common to the food sovereignty movement</a>. Food sovereignty refers to the right for people to define their own food and agriculture systems and produce healthy and culturally appropriate food using ecologically sound and sustainable practices.</p>
<p>Food sovereignty puts community first, prioritizing local and regional food needs. Notably, Canada’s supply management system has been recognized as an <a href="https://www.nfu.ca/campaigns/supply-management/">important institution of food sovereignty</a> by the National Farmers Union because of its defense of local food production.</p>
<p>Canada’s supply management system also contributes to rural sustainability. Smaller dairy (an average farm size of 88 milking cows) and egg (an average farm size of 23,000 laying hens) farms provide a stability on rural concession roads that is unmatched when they are adequately supported. </p>
<p><a href="https://www.eggfarmers.ca/wp-content/uploads/2019/02/2019-02-20_Strengthening-Canadas-rural-economies.pdf">Supply-managed farms outshine their counterparts</a> in the hog, beef and oilseeds/grains sectors by making more investments, creating more jobs and contributing more to the GDP per farm.</p>
<h2>Fairer production</h2>
<p>Canada’s current supply management model works well for both consumers and producers. Producers reap the rewards of a system that ensures farmers are paid fair prices for their products, covering the costs of production. Meanwhile, consumers enjoy the benefits of a stable supply of eggs, safeguarding them from significant price fluctuations.</p>
<p>Supply management is a legitimate tool for co-ordinating production with demand and <a href="https://www.cirano.qc.ca/files/publications/2011DT-01.pdf">avoiding overproduction and waste</a> — two chronic issues that have plagued the United States and Europe, despite significant price supports, subsidies, government purchase programs and import restrictions.</p>
<p>In today’s economic landscape, ensuring food affordability is as critical as ever. Despite worldwide inflation, <a href="https://www.ctvnews.ca/business/food-inflation-how-canada-s-grocery-prices-compares-to-other-nations-1.6425009">Canada had the second-lowest food inflation rate in the world</a> at 8.9 per cent over the year from June 2022. This stands in contrast to the 19.6 per cent increase in the United Kingdom and the European Union, Hungary’s 45.1 per cent and Argentina’s staggering 95 per cent.</p>
<h2>Farmer wages</h2>
<p>The connection between fair farmer incomes and food sustainability and sovereignty must be emphasized.</p>
<p>If food producers can’t make a living, they will leave the industry and cause catastrophic consequences. This is already happening in some places. In the U.K., rising production costs and lower farm prices <a href="https://www.theguardian.com/business/2023/jul/29/uk-dairy-farmers-costs-milk-price-energy-feed-bills">are forcing farmers out of the industry</a> and jeopardizing the U.K.’s self-sufficiency in the dairy sector.</p>
<p>In Australia, <a href="https://www.weeklytimesnow.com.au/agribusiness/dairy/dairy-farmers-leaving-industry-amid-major-loss-of-confidence/news-story/895e4ac0662678640937beed170ceaa0">farmers are leaving dairy by the thousands</a> because of price crashes. Meanwhile, in New Zealand, the world’s largest exporter of dairy, <a href="https://www.stuff.co.nz/business/farming/agribusiness/131610390/indebted-dairy-farmers-in-for-a-tough-time-as-milk-price-weakens-while-costs-go-nuts">the livelihoods of dairy farmers remain precarious</a>. Egg prices in New Zealand increased year-over-year <a href="https://www.rnz.co.nz/news/national/492153/here-s-why-egg-prices-are-still-climbing-according-to-the-industry">by 75 per cent in June</a>.</p>
<p>Even in the U.S., <a href="https://edairynews.com/en/selling-cows-dairy-farmers-business/">the story is similar</a>. Rapidly rising input costs like fuel, insurance, feed prices and labour costs, combined with stagnant or lower milk prices, have led farmers to depart that industry.</p>
<p>As supermarkets, middlemen and global food corporations pay farmers less and input costs go up, this situation has been aptly called “<a href="https://www.stuff.co.nz/business/farming/opinion/300590422/higher-farming-costs-will-quickly-start-eating-into-dairy-profits">a cost of farming crisis</a>.”</p>
<h2>Deregulation threatens sustainability</h2>
<p>The recent passage of Bill C-282, and the discussion of the bill in the Senate, presents an opportunity to reflect on the importance of food systems that serve to enhance Canadian food sustainability, security and sovereignty. As the earlier international examples make clear, deregulation in dairy farming has not led to vibrant, sustainable industries, but quite the opposite. </p>
<p>Further proof is highlighted by <a href="https://www.theguardian.com/environment/2023/jan/31/us-dairy-policies-hurt-small-farms-monopolies-get-rich">food policy analysts in the U.S.</a> who are calling on the government to reform dairy policies they argue have caused “devastating farmer loss and hardship, and a worsening environmental outlook.” </p>
<p>A recent <a href="https://www.foodandwaterwatch.org/2023/01/31/new-report-exposes-corporate-monopolies-driving-u-s-dairy-crisis/">Food and Water Watch report</a> illustrates how U.S. dairy policies centred around export markets have hurt family-sized farms by slashing on-farm profits, encouraging extreme industry consolidation and increasing environmental degradation and exploitative practices of resources. </p>
<p>Bill C-282 attempts to protect a domestic system that rejects this model. Policymakers and all Canadians should work to support systems that allow for valuable food industries to flourish, rather than dismantle them.</p><img src="https://counter.theconversation.com/content/214056/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bruce Muirhead receives funding from Egg Farmers of Canada.</span></em></p><p class="fine-print"><em><span>Jodey Nurse has received funding from Egg Farmers of Canada in the past. Her current work is not funded by them.</span></em></p>If Canada wishes to preserve domestic farms and enhance food security, officials must have limits on what they can concede to American and other foreign interests.Bruce Muirhead, Professor of History and Egg Farmers of Canada Chair in Public Policy, University of WaterlooJodey Nurse, Faculty Lecturer, McGill Institute for the Study of Canada, McGill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2119172023-09-21T02:29:20Z2023-09-21T02:29:20ZCurious Kids: what came first, the chicken or the egg?<figure><img src="https://images.theconversation.com/files/549468/original/file-20230921-15-j14ijn.png?ixlib=rb-1.1.0&rect=92%2C16%2C5497%2C4232&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock/Edited by The Conversation</span></span></figcaption></figure><blockquote>
<p><strong>What came first, the chicken or the egg? — Grace, age 12, Melbourne</strong></p>
</blockquote>
<p><a href="https://theconversation.com/au/topics/curious-kids-36782"><img src="https://images.theconversation.com/files/291898/original/file-20190911-190031-enlxbk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=90&fit=crop&dpr=1" width="100%"></a></p>
<p>Hi Grace!</p>
<p>Thanks for this great question. It’s an age-old dilemma that has left many people scratching their heads. </p>
<p>From an evolutionary perspective, both answers could be considered true! It all depends on how you interpret the question.</p>
<h2>The case for the egg</h2>
<p>When the first vertebrates – that is, the first animals with backbones – came out of the sea to live on land, they faced a challenge. </p>
<p>Their eggs, similar to those of modern fish, were covered only in a thin layer called a membrane. The eggs would quickly dry up and die when exposed to air. Some animals such as amphibians (the group that includes frogs and axolotls) solved this problem by simply laying their eggs in water – but this limited how far inland they could travel. </p>
<p>It was the early reptiles that evolved a key solution to this problem: an egg with a protective outer shell. The first egg shells would have <a href="https://phys.org/news/2020-06-hard-eggshells-evolved-dinosaur-family.html">been soft and leathery</a> like the eggs of a snake or a sea turtle. Hard-shelled eggs, such as those of birds, likely appeared much later. </p>
<p>Some of the <a href="https://www.nature.com/articles/s41598-019-40604-8">oldest known hard-shelled eggs</a> appear in the fossil record during the Early Jurassic period, roughly 195 million years ago. Dinosaurs laid these eggs, although reptiles such as crocodiles were also <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0171919">producing hard-shelled eggs</a> during the Jurassic.</p>
<p>As we know now, it was a line of dinosaurs that eventually gave rise to the many species of birds we see today, including the chicken. </p>
<p>Chickens belong to an order of birds known as the Galliformes, which includes other ground-dwelling birds such as turkeys, pheasants, peafowl and quails. </p>
<p>Specifically, chickens are part of a galliform genus called <em>Gallus</em>, which is thought to have started changing into its modern species between 6 million and 4 million <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7014787/">years ago in South-East Asia</a>. Domestic chickens only began appearing some time within the <a href="https://www.smithsonianmag.com/smart-news/researchers-pinpoint-date-when-chickens-were-first-domesticated-180980212">past 10,000 years</a>.</p>
<p>This means hard-shelled eggs like the ones chickens lay are older than chickens themselves by almost 200 million years. So problem solved, right? </p>
<p>Well, it’s a matter of perspective.</p>
<h2>The case for the chicken</h2>
<p>If we interpret the question as referring specifically to chicken eggs – and not all eggs – the answer is very different.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/549469/original/file-20230921-24-bdrveo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">No fowl play here.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Unlike most species of animals, the modern chicken didn’t evolve naturally through evolution. Rather, it’s the result of domestication: a process where humans selectively breed animals to create individuals that are more tame and have more desirable traits.</p>
<p>The most famous example is the domestication of wolves into dogs by humans. Wolves and dogs have <a href="https://www.scientificamerican.com/article/how-wolf-became-dog/">almost entirely the same DNA</a>, but are very different in how they look and behave. Dogs came from wolves, and so scientists consider dogs to be a subspecies of wolf.</p>
<p>Similarly, chickens came from a species called the red junglefowl, which is found across Southern and South-East Asia. Researchers think red junglefowl were first drawn to humans thousands of years ago, when <a href="https://www.arch.ox.ac.uk/article/major-new-international-research-reveals-new-evidence-about-when-where-and-how-chickens-were">people started farming</a> rice and other cereal grains. </p>
<p>This closeness then allowed domestication to take place. Over many generations the descendants of these tamed birds became their own subspecies. </p>
<p>Technically, the first chicken would have hatched from the egg of a selectively bred junglefowl. It was only when this chicken matured and started reproducing that the first true chicken eggs were laid.</p>
<h2>So which answer is the better one?</h2>
<p>That’s completely up to you to decide. As is the case with many dilemmas, the whole point of the question is to make you think – not necessarily to come up with the perfect answer. </p>
<p>In this case, evolutionary biology allows us to make an argument for both sides – and that is one of the wonderful things about science.</p><img src="https://counter.theconversation.com/content/211917/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ellen K. Mather does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Evolutionary biology and the fossil record reveal a great deal about the origins of chickens and eggs.Ellen K. Mather, Adjunct Associate Lecturer in Palaeontology, Flinders UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2078372023-07-06T20:21:44Z2023-07-06T20:21:44ZEggs are so expensive right now. What else can I use?<figure><img src="https://images.theconversation.com/files/534516/original/file-20230628-21-na5m3.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C1279%2C852&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.pexels.com/photo/a-man-in-a-black-shirt-cracking-an-egg-6944027/">Vlada Karpovich/Pexels</a></span></figcaption></figure><p>The price of eggs <a href="https://www.abc.net.au/news/2023-06-14/egg-shortage-high-prices-blamed-on-shift-from-cage-to-free-range/102474282">is rising</a>. So many of us may be looking for cheaper alternatives. </p>
<p>First, the bad news. Nothing can replace a boiled, poached or fried egg. </p>
<p>Now, the good news. Lots of other ingredients can make foods puff and rise, give your meal a rich taste, or hold together ingredients.</p>
<p>So try using some of these egg substitutes and save the real eggs for your breakfast.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-save-50-off-your-food-bill-and-still-eat-tasty-nutritious-meals-184152">How to save $50 off your food bill and still eat tasty, nutritious meals</a>
</strong>
</em>
</p>
<hr>
<h2>Why are eggs so popular?</h2>
<p>Eggs are incredibly <a href="https://www.foodstandards.gov.au/science/monitoringnutrients/afcd/pages/default.aspx">nutritious</a>. They’re a <a href="https://www.mdpi.com/2072-6643/11/3/684">rich source</a> of protein, vitamins A and D, pigments called carotenoids, and minerals.</p>
<p>Eggs are also versatile. We use them to make a range of savoury and sweet foods, sauces and drinks, not to mention breakfast.</p>
<p>Their popularity and versatility lies in the unique characteristics of the two main parts of the egg – the white and yolk. Each contribute <a href="https://www.amazon.com.au/Food-Cooking-Harold-McGee/dp/0684800012">different properties</a> in cooking.</p>
<p><a href="https://www.mdpi.com/2072-6643/11/3/684">Egg yolk</a> is about 55% water, 27% fats, 16% protein (with small amounts of carbohydrate). <a href="https://www.mdpi.com/2072-6643/11/3/684">Egg white</a> is about 10% protein and 90% water, with only traces of fat and carbohydrates. Different types of protein in egg white contribute to them foaming when whisked.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/five-foods-that-used-to-be-bad-for-you-but-now-arent-50333">Five foods that used to be bad for you ... but now aren't</a>
</strong>
</em>
</p>
<hr>
<h2>Eggs are versatile</h2>
<p>Eggs have a <a href="https://www.sciencedirect.com/science/article/pii/S0268005X2200131X?casa_token=1yXlEb1uvwQAAAAA:s3h5KCozwn-hjIn6kLOEoW45An255V6Z0G8TcJAQgTejfLEwV7nKqkS6VPWXiNkNxR4m5Mr2lHc">different role</a> in different types of cooking.</p>
<p><strong>1. Eggs are a raising agent</strong></p>
<p>Beaten or whisked eggs act as a raising agent by creating pockets of air in foods, which expand with cooking, making the foods puff and rise. This gives baked products like cakes, biscuits and muffins volume and an airy feel. </p>
<p>Using just the egg white leads to a remarkably light and delicate foam, as we see in meringues. In mousse and souffles the whites and the yolk are beaten separately, then mixed together. This leads to a light, airy and smooth texture. </p>
<p><strong>2. Eggs hold together other ingredients</strong></p>
<p>Eggs combine ingredients and hold them together during cooking. This gives foods – such as vegetable or meat patties – their structure.</p>
<p><strong>3. Eggs bind other liquids</strong></p>
<p>The liquid from eggs binds other liquids from other ingredients in the recipe into a soft, moist and tender mass. We see this in scrambled eggs, omelettes and egg custard.</p>
<p><strong>4. Eggs act as emulsifiers</strong></p>
<p>The egg yolk contains different proteins (livetin, phosvitin) and lipoproteins (lecithin). These act as emulsifiers, allowing fat and water to mix together in foods such as mayonnaise and hollandaise sauce.</p>
<p><strong>5. Eggs boost flavour</strong></p>
<p>The fat in egg yolks helps carry and release the flavour of some fat-soluble components of food. These foods <a href="https://www.sciencedirect.com/science/article/pii/S0924224401000796">may taste differently</a> without the eggs. Eggs also contribute to foods feeling soft in the mouth.</p>
<p>As eggs have different roles in cooking, you may need different egg substitutes depending on the outcome you want. Here are some cheaper (and vegan) options.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/eight-cracking-facts-about-eggs-150797">Eight cracking facts about eggs</a>
</strong>
</em>
</p>
<hr>
<h2>Aquafaba</h2>
<p>Aquafaba is the liquid drained from cans of bean – typically from chickpeas as it has the most neutral flavour. This is the all-round winner, especially as most of us probably throw it away without realising what a gem it is. </p>
<p>Aquafaba is <a href="https://www.sciencedirect.com/science/article/pii/S0924224421001424?casa_token=P45Z4G2SFdsAAAAA:DRy8adcAU_QHl96LONyWOEhUXvrExVZsJ18xKvc8OiPYeVKHSOkGOKefiixXFPY9UhdscEaHF70">versatile</a>. You can whip it up like egg whites to form a foam that can be used to make meringue (even pavlova), gelato, in baked goods, and for binding ingredients in patties. It also contains emulsifiers and can be used to make mayonnaise.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Chickpeas in strainer sitting over glass of aquafaba" src="https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/534518/original/file-20230628-15-2hvg8r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Aquafaba is the liquid drained from cans of beans, usually chickpeas.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/close-aquafaba-filtered-chickpea-broth-used-1907028793">Shutterstock</a></span>
</figcaption>
</figure>
<p>You’ll need different quantities of aquafaba depending on the recipe. Generally, though, you use about two to three tablespoons of aquafaba to replace the volume of fluid from an egg.</p>
<p>On the downside, aquafaba can taste a bit beany. So it is best to use it with stronger flavours to overcome this.</p>
<p>Nutritionally, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0924224421001424?via%3Dihub">aquafaba</a> has small amounts of carbohydrate (about 2.6g/100 millilitre), and negligible levels of protein (about 1.3g/100 millilitre). </p>
<p>You can also freeze aquafaba.</p>
<h2>Vinegar and baking soda</h2>
<p>Mixing a teaspoon of baking soda with a tablespoon of vinegar can replace an egg in most baked goods. This produces carbon dioxide, which is trapped into air pockets, and makes foods rise.</p>
<p>This is a very cheap option, however its success may be limited by how heavy the rest of the ingredients are. This combination also has very little nutritional value.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/is-apple-cider-vinegar-really-a-wonder-food-86551">Is apple cider vinegar really a wonder food?</a>
</strong>
</em>
</p>
<hr>
<h2>Commercial egg replacements</h2>
<p>These are available at most supermarkets, are very cheap compared with eggs, have a long shelf life, and are easy to use, with instructions on the packaging.</p>
<p>Typically, they contain different starches from potato, tapioca and pea protein (which act as leavening agents and form foams), along with raising agents. They are recommended for use in baked goods. However they have very little nutritional value compared to an egg.</p>
<h2>Flaxseed meal and chia seeds</h2>
<p>Use either a tablespoon of flaxseed meal, or chia seeds, added to about three tablespoons of water. Allow the mixture to sit for a few minutes to form a gel. </p>
<p>The gels can be used in baked goods, however this option isn’t as cheap as the others, and has a slight nutty taste. </p>
<p>Both these seeds provide nutritional value. They are both rich in the plant-based omega-3 fatty acid called alpha-linolenic acid. We <a href="https://academic.oup.com/ajcn/article/59/6/1304/4715808">can convert</a> this fatty acid into healthy omega-3 fatty acids, but at a slow rate. These seeds also provide fibre, polyphenols and antioxidants.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Chia seeds in a bowl, in a spoon, spilling onto surface" src="https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/534946/original/file-20230630-27-kgb8rn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You can add chia seeds to water to form a gel.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/healthy-chia-seeds-wooden-spoon-on-331447064">Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/does-tiktoks-chia-lemon-internal-shower-really-beat-constipation-heres-what-science-says-188744">Does TikTok's chia-lemon 'internal shower' really beat constipation? Here's what science says</a>
</strong>
</em>
</p>
<hr>
<h2>Tofu</h2>
<p>Tofu, which is made from soybeans, is widely available and fairly cheap. It has the most “eggy” appearance and so makes it ideal as a substitute for scrambled eggs and in quiche. However, you will need to use silken tofu and puree it. </p>
<p>Tofu is highly nutritious and provides protein, fat, calcium, polyphenols and anti-oxidants. </p>
<p>You could also use soy flour. Add one tablespoon to three tablespoons of water, then use immediately in baking and for binding ingredients together. However, soy flour does not contain calcium, which tofu does.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/is-fake-meat-healthy-and-whats-actually-in-it-187532">Is fake meat healthy? And what's actually in it?</a>
</strong>
</em>
</p>
<hr>
<h2>Mashed fruit</h2>
<p>Mashed bananas or applesauce are also used as egg substitutes. These mainly act to bind and hold moisture in the food and help carry the flavours. </p>
<p>You also get the nutritional value of the fruit. Due to the natural sugar that in fruit, this will sweeten your baked goods so you will need to drop the sugar by about a tablespoon (or more) for each piece of fruit you add.</p><img src="https://counter.theconversation.com/content/207837/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Evangeline Mantzioris is affiliated with Alliance for Research in Nutrition, Exercise and Activity (ARENA) at the University of South Australia. Evangeline Mantzioris has received funding from the National Health and Medical Research Council, and has been appointed to the National Health and Medical Research Council Dietary Guideline Expert Committee.</span></em></p>There are lots of other ingredients you can use to make foods puff and rise, give your meal a rich taste, or to hold together ingredients.Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, Accredited Practising Dietitian, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2070082023-06-13T06:26:48Z2023-06-13T06:26:48ZDon’t believe the hype. ‘Egg timer’ tests can’t reliably predict your chance of conceiving or menopause timing<figure><img src="https://images.theconversation.com/files/530788/original/file-20230608-27-rgqeqd.jpg?ixlib=rb-1.1.0&rect=0%2C603%2C4025%2C2408&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/AeZncpkqMVU">Caleb George/Unsplash</a></span></figcaption></figure><p>Many women who want to have children and are getting older worry about their fertility. The “egg timer” blood test is <a href="https://bmjopen.bmj.com/content/11/7/e046927">marketed</a> as an empowering way to give women insights to help them plan when to have children. </p>
<p>Online companies are now also selling the test directly to consumers to do at home, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0277953619306926">promoting the test</a> as a way for women to decide when to have a baby, even if they aren’t thinking of having one any time soon.</p>
<p>But it <a href="https://www.frontiersin.org/articles/10.3389/fendo.2021.695157/full">can’t reliably predict</a> the <a href="https://jamanetwork.com/journals/jama/fullarticle/2656811">likelihood of pregnancy</a> or how long it would take to get pregnant. </p>
<p>Despite this, egg timer testing is promoted to women not undergoing IVF as a way to assess their current and future fertility. </p>
<p>Our <a href="http://dx.doi.org/10.1136/bmjopen-2020-046927">analysis</a> of Australian and New Zealand fertility clinic websites found some claimed the test could predict a woman’s chance of conceiving or identify women at risk of early menopause.</p>
<h2>What can and can’t the test do?</h2>
<p>The test measures the level of anti-Mullerian hormone (AMH) in the blood and is known clinically as an AMH test. </p>
<p>AMH is produced by follicles in the ovaries (little fluid-filled sacs that contain immature eggs) and helps follicles and eggs grow during the menstrual cycle. Because the number of follicles in the ovaries drops with increasing age, the level of AMH also falls.</p>
<figure class="align-right ">
<img alt="African-Australian woman puts headphones on" src="https://images.theconversation.com/files/530789/original/file-20230608-19-jdt55.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/530789/original/file-20230608-19-jdt55.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/530789/original/file-20230608-19-jdt55.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/530789/original/file-20230608-19-jdt55.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/530789/original/file-20230608-19-jdt55.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/530789/original/file-20230608-19-jdt55.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/530789/original/file-20230608-19-jdt55.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">AMH testing can be used to indicate whether a medical condition or treatment, such as chemotherapy, has affected a woman’s ovarian reserve.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/d7JCyFstmqM">Dushawn Jovic/Unsplash</a></span>
</figcaption>
</figure>
<p>The AMH level <a href="https://doi.org/10.1530/EJE-19-0373">indicates</a> the number of eggs in the ovaries, or ovarian reserve. </p>
<p>It is often used in IVF treatment, as it <a href="https://doi.org/10.1093/humupd/dms041">can suggest</a> how many eggs a woman may get when her ovaries are stimulated with fertility drugs. </p>
<p>But it can’t tell you anything about egg quality. Women with low AMH levels have the <a href="https://jamanetwork.com/journals/jama/fullarticle/2656811">same chance</a> of conceiving as women with normal AMH levels.</p>
<p>It also <a href="https://academic.oup.com/humupd/article/29/3/327/6990969">can’t reliably predict</a> menopause <a href="https://pubmed.ncbi.nlm.nih.gov/30032277/">timing</a> for individual women. </p>
<p>Because of this, the American College of Obstetricians and Gynaecologists <a href="https://pubmed.ncbi.nlm.nih.gov/30913192/">strongly discourages</a> AMH testing in women who are not seeking fertility treatment. It states the test:</p>
<blockquote>
<p>should not be ordered or used to counsel women who are not infertile about their reproductive status and future fertility potential. </p>
</blockquote>
<p>No similar guidance has been published by the relevant colleges in Australia. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/womens-fertility-does-egg-timer-testing-work-and-what-are-the-other-options-109726">Women's fertility: does 'egg timer' testing work, and what are the other options?</a>
</strong>
</em>
</p>
<hr>
<h2>Who gets AMH tests and why?</h2>
<p>The test isn’t Medicare-subsidised. Most AMH tests are paid for privately by consumers, costing around A$80-$120. Because of this, data on current test usage is not publicly available. </p>
<p>To find out how many women in Australia are accessing AMH testing and why, we conducted the <a href="https://academic.oup.com/humrep/advance-article/doi/10.1093/humrep/dead111/7193900?searchresult=1">first investigation</a> into its use in Australia.</p>
<p>We surveyed a representative sample of 1,773 women aged 18 to 55, recruited through the <a href="https://srcentre.com.au/our-research/life-in-australia-study">Life in Australia</a> national study.</p>
<p>We asked them if and how they had heard about AMH testing, whether they had ever had an AMH test, their main reason for testing and how they accessed the test.</p>
<figure class="align-center ">
<img alt="Woman in jeans sits, cross-legged" src="https://images.theconversation.com/files/530791/original/file-20230608-25-2bax4c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/530791/original/file-20230608-25-2bax4c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/530791/original/file-20230608-25-2bax4c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/530791/original/file-20230608-25-2bax4c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/530791/original/file-20230608-25-2bax4c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/530791/original/file-20230608-25-2bax4c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/530791/original/file-20230608-25-2bax4c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">We asked Australian women about their use of AMH testing.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/L1kLSwdclYQ">Imani Bahati/Unsplash</a></span>
</figcaption>
</figure>
<p>Our results, published today, show 13% of the women had heard about AMH testing and 7% had had an AMH test.</p>
<p>The majority had the test for medically indicated reasons, such as during infertility investigations (51%), or to find out if a medical condition had affected their fertility (11%). This included having had chemotherapy or radiotherapy, endometriosis, thyroid issues, and others.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/young-people-with-cancer-should-have-affordable-options-to-preserve-their-fertility-63457">Young people with cancer should have affordable options to preserve their fertility</a>
</strong>
</em>
</p>
<hr>
<p>Concerningly, one-third reported having had the test for other reasons. This included gaining insights into their fertility or inform their reproductive life planning (30%). </p>
<p>Most women who had an AMH test first heard about it from their GP or fertility specialist, suggesting doctors are currently the main drivers of test uptake. </p>
<p>However this may change with the recent emergence of direct-to-consumer AMH testing in Australia, as online companies increase their marketing.</p>
<h2>What are the downsides of having an AMH test?</h2>
<p>Getting the test to inform you about your fertility may lead you to make choices based on a false premise. </p>
<p>If you get a normal or high AMH result, it may give a false sense of security about delaying pregnancy, when age is the most important factor of female fertility. </p>
<p>If you receive a low result, it may cause unwarranted anxiety about not being able to conceive. This may cause pressure to conceive earlier than desired, or create a <a href="https://www.publish.csiro.au/PY/PY18040">sense of urgency</a> and haste towards fertility treatment, such as <a href="https://doi.org/10.1080/02646838.2016.1275533">egg freezing</a>.</p>
<figure class="align-center ">
<img alt="Woman sits on her longeroom floor, looking at her laptop" src="https://images.theconversation.com/files/530792/original/file-20230608-18-n32955.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/530792/original/file-20230608-18-n32955.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/530792/original/file-20230608-18-n32955.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/530792/original/file-20230608-18-n32955.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/530792/original/file-20230608-18-n32955.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/530792/original/file-20230608-18-n32955.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/530792/original/file-20230608-18-n32955.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Women need good evidence about the limitations of AMH testing.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/Nv-vx3kUR2A">Unsplash/Thought Catalog</a></span>
</figcaption>
</figure>
<p>To make informed decisions about AMH testing, women need clear, evidence-based information. We have developed and are currently testing an evidence-based information guide to assist with this.</p>
<h2>Can other tests tell me about my fertility?</h2>
<p>Unfortunately, there is no reliable test of a woman’s fertility. </p>
<p>But it’s important to know a woman’s age is the greatest predictor of her chance of pregnancy. The only real way to know your fertility is by trying to get pregnant when you are ready.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/women-are-often-told-their-fertility-falls-off-a-cliff-at-35-but-is-that-right-189978">Women are often told their fertility 'falls off a cliff' at 35, but is that right?</a>
</strong>
</em>
</p>
<hr>
<img src="https://counter.theconversation.com/content/207008/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Tessa Copp is supported by an NHMRC Emerging Leader Research Fellowship (2009419). She is on the Scientific Committee of the Preventing Overdiagnosis Conference. </span></em></p><p class="fine-print"><em><span>Jenny Doust receives funding from Centre of Research Excellence on Women and Non-communicable Diseases (CRE-WaND) NHMRC APP1153420. </span></em></p><p class="fine-print"><em><span>Karin Hammarberg works part-time for the Victorian Assisted Reproductive Treatment Authority.</span></em></p>The ‘egg timer’ blood test is marketed as an empowering way to give women insights to help them plan when to have children. Problem is, it can’t deliver what it promises.Tessa Copp, NHMRC Emerging Leader Research Fellow, University of SydneyJenny Doust, Clinical Professorial Research Fellow, The University of QueenslandKarin Hammarberg, Senior Research Fellow, Global and Women's Health, School of Public Health & Preventive Medicine, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2055482023-05-15T12:33:24Z2023-05-15T12:33:24ZSupreme Court’s ruling on humane treatment of pigs could catalyze a wave of new animal welfare laws<figure><img src="https://images.theconversation.com/files/525957/original/file-20230512-22-a35zgz.jpeg?ixlib=rb-1.1.0&rect=18%2C12%2C4071%2C3053&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sows in gestation crates at a breeding facility in Waverly, Va.</span> <span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/thumb/5/5f/Gestation_crates_2.jpg/4096px-Gestation_crates_2.jpg">Humane Society of the U.S./Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Should California be able to require higher welfare standards for farm animals raised in other states if products from those animals are to be sold in California? On May 11, 2023, the U.S. Supreme Court upheld California’s position by a 5-4 vote in <a href="https://www.supremecourt.gov/opinions/22pdf/21-468_5if6.pdf">National Pork Producers Council v. Ross</a>. </p>
<p>While the ruling was fractured and reflected complex legal questions, it is a major victory for those working to improve farm animal welfare. A number of states will undoubtedly take advantage of the power that the Supreme Court has recognized. </p>
<p>As a <a href="https://www.law.msu.edu/faculty_staff/profile.php?prof=12">specialist in animal law</a>, I expect that this will result in a patchwork of laws that are likely to make national meat producers very uncomfortable. Ultimately, it could push Congress to set federal standards.</p>
<h2>More indoor space for sows</h2>
<p>Pork producers sued California over a law that the state’s voters <a href="https://ballotpedia.org/California_Proposition_12,_Farm_Animal_Confinement_Initiative_(2018)">adopted in 2018</a> via ballot initiative with over 63% approval. It set new conditions for raising hogs, veal calves and egg-laying chickens whose meat or eggs are sold in California. The state produces virtually no pork, but represents <a href="https://nppc.org/ca-prop-12/">about 15% of the U.S. pork market</a>. </p>
<p>At <a href="https://www.bloomberg.com/news/articles/2023-02-15/pork-prices-are-a-key-issue-in-debate-over-gestation-crates?sref=Hjm5biAW">most commercial hog farms</a>, pregnant sows are kept in pens called gestation crates that measure about 2 feet by 7 feet – enough room for the animals to sit, stand and lie down, but <a href="http://animalwelfare.ucdavis.edu/uploads/6/3/7/0/63703691/prop_12_faq_swine.pdf">not enough to turn around</a>. California’s law requires that each sow must have <a href="https://law.justia.com/codes/california/2010/hsc/25990-25994.html#:%7E:text=25990.,(b)%20Turning%20around%20freely.">at least 24 square feet of floor space</a> – nearly double the amount that most now get. It does not require farmers to raise free-range pigs; just provide more square footage for hogs in buildings. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/vQPUGU6le0s?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Pork producers in Iowa, which produces about one-third of all hogs raised in the U.S., react to the Supreme Court ruling upholding the California law.</span></figcaption>
</figure>
<p>The <a href="https://nppc.org/">National Pork Producers Council</a> argued that this requirement <a href="https://nppc.org/ca-prop-12/">imposed heavy compliance costs</a> on farmers across the U.S., since large hog farms may house <a href="https://www.nationalhogfarmer.com/reproduction/does-farm-size-matter-swine-production">thousands of sows</a>, and that it restricted interstate commerce. The Constitution’s commerce clause delegates authority to regulate interstate commerce <a href="https://www.law.cornell.edu/wex/commerce_clause">to the federal government</a>. In a series of cases over the past 50 years, the Supreme Court has made clear that it will strike down any state law that seeks to control commerce in another state or <a href="https://www.oyez.org/cases/2006/05-1345">give preference to in-state commerce</a>. </p>
<h2>States control farm animal welfare</h2>
<p>Congress has remained mute on standards for handling farm animals, which are <a href="https://www.nal.usda.gov/animal-health-and-welfare/animal-welfare-act">not covered under the 1966 Animal Welfare Act</a>. Consequently, each state regulates this issue within its borders. </p>
<p>For example, in recent years, nine states have <a href="https://blog.humanesociety.org/2021/06/breaking-nevada-becomes-ninth-state-to-ban-cages-for-egg-laying-hens.html">outlawed housing egg-laying chickens in “battery cages</a>” that have been the industry standard for decades. These wire enclosures are so small that <a href="https://archive.nytimes.com/www.nytimes.com/interactive/2010/08/15/weekinreview/15marsh-grfk.html">the birds cannot spread their wings</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Shelves lined with small wire cages, each holding multiple chickens." src="https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=407&fit=crop&dpr=1 600w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=407&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=407&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=511&fit=crop&dpr=1 754w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=511&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=511&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chickens in battery cages on an Iowa poultry farm.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/ChinaChickenTrade/d5d0a3185fab492b8d39486d57e0ed4a/photo">AP Photo/Charlie Neibergall</a></span>
</figcaption>
</figure>
<p>And <a href="https://www.ers.usda.gov/data-products/chart-gallery/gallery/chart-detail/?chartId=103505">nine states in addition to California</a> have adopted laws requiring pork producers to phase out gestation crates. Massachusetts’ law, like California’s, would also apply to retail sales of pork raised elsewhere, but <a href="https://www.foodqualityandsafety.com/article/court-orders-delay-of-massachusetts-pork-production-law/">its enforcement has been on hold</a> pending the Supreme Court’s ruling in the California case.</p>
<h2>California’s market power</h2>
<p>The California law says that if producers want to sell pork in California, they must raise pigs under conditions that comply with the state’s regulations. Farmers do not have to meet these standards unless they want to sell in California. The same requirement is applied to producers located in California and those based elsewhere, so the law does not directly discriminate between states in a way that would constitute a clear commerce clause violation.</p>
<p>Producers of <a href="https://www.poultryworld.net/poultry/cage-free-us-egg-industry-sooner-rather-than-later/">eggs</a> and <a href="https://www.agupdate.com/missourifarmertoday/news/livestock/builder-sees-producers-adapting-to-prop-12/article_f2c43598-ed80-11ec-a8bc-af01d15c519d.html">veal</a> that sell in California are on track to implement new space requirements for their animals under the law. But instead of working out how to comply, the pork industry sought to have the courts set the California law aside.</p>
<p>However, as the Supreme Court noted, major producers, including <a href="https://www.hormelfoods.com/newsroom/news/hormel-foods-company-information-about-california-proposition-12/">Hormel</a> and <a href="https://s22.q4cdn.com/104708849/files/doc_financials/2021/q3/08-11-21_Tyson-Foods-080921.pdf">Tyson</a>, have said they will be able to comply with the California standard. Niman Ranch, a network of family farmers and ranchers who raise livestock humanely and sustainably, filed an amicus brief with the Supreme Court <a href="https://www.supremecourt.gov/DocketPDF/21/21-468/233498/20220815141539359_21-468_Amicus%20Brief.pdf">supporting California</a>. </p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1656817787858296833"}"></div></p>
<h2>A fractured verdict</h2>
<p>In rejecting the pork industry’s position, justices in the majority disagreed as to why the California law should be upheld. Some held that pork producers had not proved that the law would substantially interfere with interstate commerce. Others argued that regardless of the degree of interference, it was inappropriate to ask courts to balance compliance costs for the industry against California voters’ moral concerns about animal welfare. </p>
<p>“While the Constitution addresses many weighty issues,” Justice Neil Gorsuch <a href="https://www.supremecourt.gov/opinions/22pdf/21-468_5if6.pdf">wrote for the majority</a>, “the type of pork chops California merchants may sell is not on that list.” Justices Clarence Thomas, Sonia Sotomayor, Elena Kagan and Amy Coney Barrett largely supported Gorsuch’s opinion. </p>
<p>Similarly, dissenting justices differed as to why the California law posed a constitutional problem. Justices John Roberts, Samuel Alito and Ketanji Brown Jackson asserted that the substantial interference requirement had been met, and they would have remanded the case back to the 9th Circuit Court of Appeals. Only Justice Brett Kavanaugh held that the California law should be held void because the positive animal welfare outcomes were not substantial enough to overcome the increased cost it imposed on pork producers. </p>
<h2>Beyond pork</h2>
<p>Farmers and animal welfare advocates understand that with this win, states with the most progressive animal welfare policies – primarily West Coast and Northeast states – will be able to effectively set national standards for the well-being of many agricultural animals, including chickens, dairy cows and cattle. Conceivably, California might also be able to require basic conditions for human labor, such as minimum wage standards, associated with products sold in California.</p>
<p>I expect that within five years, Congress will enact national legislation on farm animal welfare issues that will preempt differing state laws. It is impossible to predict now whether a new national law would improve animal welfare or adopt existing poor welfare practices – but California’s win represents a major victory for advocates who have sought for years to improve conditions for farm animals across the U.S.</p>
<p><em>This is an update of an <a href="https://theconversation.com/supreme-court-grapples-with-animal-welfare-in-a-challenge-to-a-california-law-requiring-pork-to-be-humanely-raised-187893">article</a> originally published October 4, 2022.</em></p><img src="https://counter.theconversation.com/content/205548/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Favre was a founding board member of the Animal Legal Defense Fund.</span></em></p>The Supreme Court has upheld a controversial California law requiring pork sold in-state to be humanely raised, no matter where it’s produced. Pork producers say it could drive up food prices.David Favre, Professor of Law, Michigan State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2012362023-03-13T16:38:55Z2023-03-13T16:38:55ZHow free-range eggs became the norm in supermarkets – and sold customers a lie<figure><img src="https://images.theconversation.com/files/514443/original/file-20230309-28-t3glwf.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5615%2C3741&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/freshly-laid-free-range-eggs-farmers-467379797">MJHeritage/Shutterstock</a></span></figcaption></figure><p>The UK is in the grip of its <a href="https://lordslibrary.parliament.uk/bird-flu-2022-dealing-with-the-uks-largest-ever-outbreak/">largest ever outbreak of bird flu</a>. As its name suggests, avian influenza primarily affects birds, but it can also infect humans and other mammals. The virus first emerged in <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5702979/">China in 1996</a> and the highly pathogenic H5N1 is the <a href="https://www.gov.uk/government/publications/avian-influenza-influenza-a-h5n1-technical-briefings/investigation-into-the-risk-to-human-health-of-avian-influenza-influenza-a-h5n1-in-england-technical-briefing-1">predominant variant</a> causing havoc <a href="https://www.bmj.com/content/380/bmj.p401">at the moment</a>. </p>
<p>The confinement and transportation of farmed birds has allowed H5N1 to spread rapidly, leaving devastation in its wake. It is not just poultry that is affected. The current outbreak is killing wildlife on an <a href="https://www.nature.com/articles/d41586-022-01338-2">unprecedented scale</a>, from <a href="https://www.rspb.org.uk/birds-and-wildlife/advice/how-you-can-help-birds/disease-and-garden-wildlife/avian-influenza-updates/">seabirds</a> in the UK to <a href="https://www.nhm.ac.uk/discover/news/2023/march/bird-flu-kills-thousands-south-american-sea-lions-outbreak-continues.html">sea lions</a> in Peru.</p>
<p>Though the UK government currently assesses the risk to the wider public as <a href="https://ukhsa.blog.gov.uk/2021/11/26/what-is-avian-flu/">very low</a>, some strains of bird flu can pass to humans after sustained close contact. The producers of David Attenborough’s latest television series had to pull plans for him to film close to seabirds on the island of Skomer for fears he might <a href="https://www.theguardian.com/tv-and-radio/2023/mar/07/producers-feared-david-attenborough-would-catch-bird-flu-and-die-during-filming">catch the disease</a>.</p>
<p>As a result of the outbreak, <a href="https://www.gov.uk/government/news/avian-influenza-housing-order-to-be-introduced-across-england">mandatory housing</a> of chickens has been in place in England since November 2022. This means that no eggs produced in England are currently “free-range”. There is no defined end to this situation and as of February, all free-range eggs have been <a href="https://www.freerangeinfo.com/">relabelled</a>. </p>
<p>Some customers are <a href="https://twitter.com/isthatamyj/status/1630952218240118785">unhappy</a> with buying eggs from chickens without access to the outdoors. But exploring the history of free-range eggs in the UK reveals why their preferred purchases may never have been that safe or ethical in the first place.</p>
<h2>The fall and rise of free-range</h2>
<p>The RSPCA defines free-range eggs as those coming “from birds that, during the daytime, enjoy <a href="https://www.rspcaassured.org.uk/rspca-assured-products/free-range-eggs/">unlimited access to outdoor pastures</a>”. Before the mid-20th century, almost all eggs in the UK were free-range. Aside from some semi-intensive systems, where chickens were kept permanently in sheds, there were no alternatives.</p>
<p>The mass adoption of battery cages from the 1950s onwards transformed the egg industry. Battery farming sees hens packed into cages to control their environment and increase the number of eggs they lay. In the UK, free-range eggs accounted for 80% of all eggs produced in 1951. By 1980, the figure was <a href="https://link.springer.com/book/10.1057/9780230599963">1%</a>.</p>
<p>The welfare of chickens kept in battery farms naturally suffered. Ruth Harrison’s 1964 book Animal Machines was among the first to reveal the cruelty of modern poultry production. </p>
<p>In it, she described the “<a href="https://www.cabidigitallibrary.org/doi/book/10.1079/9781780642840.0000">miserable and debilitated</a>” life of battery hens. This became a focal point of activism and sparked a <a href="https://discovery.nationalarchives.gov.uk/details/r/C2106199">government investigation</a> into farm animal welfare just a year later. </p>
<p>But it was not until a panic over the alleged presence of salmonella in eggs in <a href="http://news.bbc.co.uk/onthisday/hi/dates/stories/december/3/newsid_2519000/2519451.stm">1988</a> that public opinion began to change. Thanks to that and other scares, such as the outbreak of “mad cow” disease on beef farms in the 1990s, the public perception of intensively farmed food shifted from <a href="https://www.tandfonline.com/doi/abs/10.1080/09505431.2011.563574">safe to risky</a>.</p>
<figure class="align-center ">
<img alt="Hens poke their heads out of metal cages above a trough filled with eggs." src="https://images.theconversation.com/files/514445/original/file-20230309-22-1bzzvh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/514445/original/file-20230309-22-1bzzvh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/514445/original/file-20230309-22-1bzzvh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/514445/original/file-20230309-22-1bzzvh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/514445/original/file-20230309-22-1bzzvh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/514445/original/file-20230309-22-1bzzvh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/514445/original/file-20230309-22-1bzzvh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Hens raised in battery cages are unable to express their natural behaviour.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/battery-cage-layer-chickens-multilevel-production-1034569678">Mai.Chayakorn/Shutterstock</a></span>
</figcaption>
</figure>
<p>Alternative systems for producing eggs became more popular as a result. From their 1981 nadir, free-range eggs now constitute over 60% of the <a href="https://www.egginfo.co.uk/egg-facts-and-figures/industry-information/data">11.3 billion eggs</a> produced in the UK annually, according to a 2021 industry estimate.</p>
<h2>Safe and ethical?</h2>
<p>Free-range eggs are <a href="https://www.tandfonline.com/doi/abs/10.1080/08927936.2017.1310986">perceived</a> as safer by consumers and an easier ethical choice. Supermarkets offer an abundance of free-range products and there is no great difference in price compared with eggs from caged hens. </p>
<p>However, free-range egg farms differ from the advertised scenes of chickens roaming free in open fields. Even RSPCA assured free-range flocks can number <a href="https://www.rspcaassured.org.uk/rspca-assured-products/free-range-eggs/">16,000 hens</a> a shed, with daytime access to the outside provided by holes in the perimeter. </p>
<p><a href="https://www.bhwt.org.uk/beak-trimming/">Beaks are trimmed</a> to prevent birds harming each other as a result of the stress in this unnatural environment. More expensive <a href="https://www.soilassociation.org/take-action/organic-living/what-is-organic/organic-eggs/">organic eggs</a>, produced by much smaller flocks on farms where beak trimming is banned, are a <a href="https://www.egginfo.co.uk/egg-facts-and-figures/industry-information/data">minority</a> of those eaten in the UK.</p>
<p>Free-range egg farming is seen as both safer and more ethical than other forms of production. Though free from the worst excesses of battery farming, eggs with the free-range label are still produced on densely packed farms. Large, intensive systems such as these are implicated in the spread of bird flu, devastating poultry and wildlife alike. </p>
<p>Along with <a href="https://www.reuters.com/world/uk/uk-salad-shortage-weighs-supermarket-sales-niq-2023-03-07/">salad shortages</a> and “<a href="https://news.sky.com/story/milk-cheese-and-eggs-push-inflation-to-highest-rate-in-four-decades-12748651">milkflation</a>”, the disappearance of free-range eggs from English supermarkets is symptomatic of a food system responding to environmental stresses. The risks to animal welfare and the environment inherent in this system will remain without more radical changes to the scale and density of animal agriculture.</p>
<hr>
<figure class="align-right ">
<img alt="Imagine weekly climate newsletter" src="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/434988/original/file-20211201-21-13avx6y.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
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<p class="fine-print"><em><span>Joel Mead receives funding from the ESRC-funded North West Social Science Doctoral Training Partnership.</span></em></p>Though preferable to battery farms, free-range eggs are not as safe and ethical as customers think.Joel Mead, PhD Candidate in History, University of LiverpoolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1979742023-01-25T06:12:07Z2023-01-25T06:12:07ZFood shortages: five ways to fix ‘unfair’ supply chains<figure><img src="https://images.theconversation.com/files/505958/original/file-20230123-13-ci2u2d.jpg?ixlib=rb-1.1.0&rect=23%2C13%2C974%2C633&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/close-skillful-old-farmer-holding-chicken-485801590">Marian Weyo/Shutterstock</a></span></figcaption></figure><p>UK food prices soared by <a href="https://www.spectator.co.uk/article/food-price-inflation-hits-16-8-per-cent/">more than 16%</a> in 2022 as record <a href="https://www.ons.gov.uk/economy/inflationandpriceindices/articles/risingcostofpastabreadandothereverydayfoodsleavesmostvulnerabletheworstoff/2022-12-22#:%7E:text=grocery%20items%20have-,increased%20by%20more%20than%2020%25,-in%20the%20year">inflation pushed up the prices</a> of everything from bread to beans. </p>
<p>Tesco chairman John Allan recently suggested that suppliers could be using this situation <a href="https://www.bbc.co.uk/news/business-64364744">to boost prices</a>. Speaking to <a href="https://www.bbc.co.uk/programmes/m001hhxb">the BBC’s Laura Kuenssberg</a> about whether food companies were taking advantage of consumers with recent price rises, Allan said: “I think that’s entirely possible”. </p>
<p>While he admitted he hadn’t “seen their cost structures”, he said the supermarket chain was fighting “very hard to challenge cost increases”. Tesco has <a href="https://theconversation.com/three-ways-companies-change-their-products-to-hide-inflation-189924#:%7E:text=In%20July%2C%20a%20dispute%20over%20a%20price%20increase%20for%20products%20including%20tins%20of%20baked%20beans%20saw%20supermarket%20Tesco%20freeze%20its%20orders%20from%20food%20company%20Heinz.">previously refused to stock certain products</a> while haggling over prices with suppliers.</p>
<p>Allan’s comments have been <a href="https://uk.news.yahoo.com/tesco-chief-living-parallel-universe-110811635.html">criticised by food firms and farmers</a> alike. They argue that they are suffering from rising costs and often don’t see the benefits of food price hikes. </p>
<p>For example, farmers and suppliers – many of whom are <a href="https://ourworldindata.org/smallholder-food-production">small- and medium-sized firms</a> (SMEs) – have recently argued they are not getting <a href="https://library.myebook.com/CILT/focus-november-2021/3697/#page/25">a fair price for their eggs</a> from supermarkets and other big-box stores. The price of a dozen eggs at the till rose by 45p over the course of 2022, but many farmers only saw 5p-10p of that rise, according to <a href="https://www.bfrepa.co.uk/media-centre/news/statement-to-bbc-and-others/103">figures released in November by the British Free Range Egg Producers Association</a>. </p>
<p>Combined with rapidly rising <a href="https://www.ons.gov.uk/economy/inflationandpriceindices/bulletins/producerpriceinflation/october2022">production costs</a> and the impact of the <a href="https://www.france24.com/en/environment/20230113-largest-global-bird-flu-outbreak-in-history-shows-no-sign-of-slowing">worst avian flu pandemic in history</a>, this is putting enormous strain on these producers and suppliers. And the current combination of rising interest rates and high input and energy costs is <a href="https://www.purdue.edu/newsroom/releases/2022/Q4/high-input-costs-and-rising-interest-rates-top-concerns-as-farmer-sentiment-remains-unchanged.html">generating concern</a> among farmers in general. </p>
<p>In this rising price environment, these businesses are at risk of further pressure on their cash flows or even future production failure. This could eventually impact the UK’s <a href="https://library.myebook.com/CILT/focus-april-2022/3982/#page/47">food supply chain resilience</a> and security, and also increase waste.</p>
<figure class="align-center ">
<img alt="Empty eggs shelves supermarket store. Food supply shortage crisis." src="https://images.theconversation.com/files/506081/original/file-20230124-12-u3basp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506081/original/file-20230124-12-u3basp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=310&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506081/original/file-20230124-12-u3basp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=310&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506081/original/file-20230124-12-u3basp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=310&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506081/original/file-20230124-12-u3basp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=390&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506081/original/file-20230124-12-u3basp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=390&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506081/original/file-20230124-12-u3basp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=390&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Some supermarkets were forced to ration eggs in 2022 due to supply chain issues.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/coronavirus-panic-buying-concept-eggs-shelves-1674343042">MIA Studio/Shutterstock</a></span>
</figcaption>
</figure>
<p>Indeed, producers and suppliers can face a significant power imbalance in food supply chains, which can feed through to higher prices for consumers. While such businesses often bear all the risks of producing and supplying items like eggs, many are unable to bargain for more favourable trading terms with powerful retailers. </p>
<p>Our <a href="https://doi.org/10.1108/JOPP-05-2021-0032">previous research</a> suggests small businesses in other industries also have little or no bargaining power in such situations. These businesses must adhere to the terms imposed by their buyers, or risk losing income. </p>
<p>Supporting <a href="https://www.tandfonline.com/doi/full/10.1080/00207543.2021.1928319">supply chain fairness</a> will not only safeguard these companies from collapse, it will also help relieve shortages for consumers and could prevent future food supply crises.</p>
<h2>Fairness in supply chains</h2>
<p>The concept of “<a href="https://doi.org/10.1007/s10551-007-9350-3">fairness</a>” is frequently overlooked in discussions about <a href="https://hbr.org/2020/03/a-more-sustainable-supply-chain">supply chain sustainability</a>, perhaps because it is so subjective. When <a href="https://www.sciencedirect.com/science/article/pii/S0065260108601082">evaluating fairness in any exchange</a>, one party compares their inputs and outputs, and what they believe they deserve. </p>
<p>These decisions usually come down to <a href="https://journals.sagepub.com/doi/10.1177/0149206308330557">context</a>, being shaped by the nature of the exchange and any previous interactions with the other party. </p>
<p>While the concept of fairness is rarely included in the <a href="https://sdgs.un.org/goals">sustainability agenda</a> of an organisation, in a <a href="https://www.storre.stir.ac.uk/retrieve/0ca33640-beee-4451-9805-1818ab63b465/Oyedijo-etal-HarrySusilopaper-2018.pdf">supply chain context</a> the <a href="https://doi.org/10.1016/j.jom.2012.03.003">fundamentals of fairness</a> can be <a href="https://onlinelibrary.wiley.com/doi/full/10.1016/j.jom.2013.05.001">measured</a> using three key dimensions: </p>
<ul>
<li>the economic returns derived from the relationships;</li>
<li>how decisions are governed, as well as the policies and procedures related to the relationships;</li>
<li>the extent to which the other party communicates relevant information and resolves conflicts with openness. </li>
</ul>
<figure class="align-center ">
<img alt="Close up hand of business person shaking hands with partner, fair play." src="https://images.theconversation.com/files/506082/original/file-20230124-25-a6vrmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/506082/original/file-20230124-25-a6vrmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/506082/original/file-20230124-25-a6vrmb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/506082/original/file-20230124-25-a6vrmb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/506082/original/file-20230124-25-a6vrmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/506082/original/file-20230124-25-a6vrmb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/506082/original/file-20230124-25-a6vrmb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Playing fair.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/concept-negotiating-business-handshake-gesturing-people-1189702330">Joke Phatrapong/Shutterstock</a></span>
</figcaption>
</figure>
<p>Based on these measures, our recent research has produced five strategies that could help promote food supply chain fairness:</p>
<h2>1. Revisiting the terms of trade</h2>
<p>Given the relative <a href="https://doi.org/10.1007/s10551-021-04791-7">weakness of suppliers</a>, it is essential to re-evaluate their contract terms with supply chain partners and ensure that these terms allocate profits or benefits equally. In supply agreements, it is essential to provide clear and unambiguous terms of trade. These business terms require legal enforcement and repercussions.</p>
<h2>2. Alignment across the food supply chain</h2>
<p>The supply chain may be misaligned when it comes to the ethical values and practices of the various participants, allowing unfair practices to persist. One way to address this is to foster mutual understanding, standard practice and value among all stakeholders in the supply chain. This can be achieved through <a href="https://doi.org/10.1108/SCM-06-2020-0263">risk sharing</a>, relationship building, and dedicated investments that benefit the entire chain.</p>
<h2>3. Lobbying and advocacy</h2>
<p>Suppliers as a whole need to send messages that will move relevant authorities and government agencies to take concrete steps toward implementing policy changes. Such bodies include the <a href="https://www.nfuonline.com/">National Farmers’ Union</a>, <a href="https://www.fdf.org.uk/">the Food and Drink Federation</a> and the <a href="https://www.gov.uk/government/organisations/department-for-environment-food-rural-affairs">Department for Environment, Food and Rural Affairs</a>, as well as more general groups such as the <a href="https://www.fsb.org.uk/">Federation of Small Businesses</a> and the <a href="https://www.cbi.org.uk/">Confederation of British Industry</a>.</p>
<h2>4. Addressing the power imbalance</h2>
<p>It is crucial to bring back <a href="https://www.jstor.org/stable/1236903">agricultural marketing boards</a> – government entities that oversee agricultural production and compliance. These organisations could help put producers and distributors of agri-food commodities on an equal footing with retailers when it comes to bargaining. Government action, in the form of policy reviews and adjustments to the existing structures for procurement and supply chains, would also help. The concept of fairness should also be incorporated into the sourcing and supplier relationship practices of large retailers.</p>
<h2>5. Education to raise standards</h2>
<p>All supply chain members need ethical supply chain management education to raise industry standards. UK professional bodies like the <a href="https://www.cips.org/">Chartered Institute of Procurement and Supply</a> and the <a href="https://ciltuk.org.uk/">Chartered Institute of Logistics and Transport</a> could help regulators and supply chain members develop the right skills, knowledge and new perspectives. </p>
<p>Implementing these five strategies will require all supply chain members to take these necessary steps.</p>
<p>With rising demand for food and a growing global population, it is more important than ever to <a href="https://www.ipt.org.uk/newsroom/details/Event-Blog-Building-Resilient-Food-Supply-Chains">build a resilient food supply chain</a>. Our research shows that <a href="https://www.theguardian.com/business/2022/dec/06/uk-food-supply-crisis-farmers-nfu-fuel-fertiliser-feed">preventing a food crisis in the UK</a> means <a href="https://www.weforum.org/agenda/2019/07/fairness-agricultural-goods-trade-partnerships/">placing fairness</a> at the heart of our food supply chains.</p><img src="https://counter.theconversation.com/content/197974/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Adegboyega Oyedijo is a Chartered Member of both the Chartered Institute of Procurement and Supply (CIPS) and the Chartered Institute of Logistics and Transport (CILT).</span></em></p><p class="fine-print"><em><span>Temidayo Akenroye does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Research shows that food supply chains are unfair, but there are ways to make them more sustainable for all involved.Adegboyega Oyedijo, Lecturer in Operations and Supply Chain Management, University of LeicesterTemidayo Akenroye, Associate Professor of Supply Chain & Analytics, University of Missouri-St. LouisLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1977702023-01-12T23:56:10Z2023-01-12T23:56:10ZInflation report is a mixed bag – an economist explains why some items are rising faster than others<figure><img src="https://images.theconversation.com/files/504331/original/file-20230112-69985-mrta08.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5991%2C3979&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Oeuf! Egg prices are rising faster than a souffle.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/homemade-souffle-with-sugar-powder-royalty-free-image/680175794?phrase=souffle&adppopup=true">Getty Images</a></span></figcaption></figure><p><em>Economists worried about soaring inflation got some good news to start the year: The rate of inflation has eased. The <a href="https://www.reuters.com/markets/us/us-consumer-prices-fall-december-weekly-jobless-claims-edge-down-2023-01-12/">first report card of 2023 on consumer prices</a>, released on Jan. 12, showed that the overall cost of goods and services decelerated to an annual pace of 6.5% in December, the <a href="https://fred.stlouisfed.org/series/CPIAUCSL#">slowest in over a year</a> and down from 7.1% in November.</em></p>
<p><em>But there’s bad news too, especially if you are an <a href="https://fred.stlouisfed.org/series/APU0000708111#0">egg-munching</a> <a href="https://fred.stlouisfed.org/series/CUUR0000SAS2RS#0">renter</a> fond of frequent <a href="https://fred.stlouisfed.org/series/CUUR0000SEGB#0">regular haircuts</a>. In quite a few categories, the cost of living rose at an even faster pace.</em></p>
<p><em>That’s because price inflation isn’t uniform. Different products and services are affected by myriad factors. So while some prices may have fallen during December, slowing the annual rate of inflation, other items kept getting more expensive.</em></p>
<p><em>The Conversation asked Edouard Wemy – an <a href="https://www2.clarku.edu/faculty/facultybio.cfm?id=1080">economist from Clark University</a> who never sets off to work without his morning breakfast of two eggs, sunny side up – to explain how different items in the consumer price basket fared in the latest inflation report.</em></p>
<h2>Energy</h2>
<p>When you look at the detail of the latest report on the consumer price index, you’ll see that overall energy costs declined. That’s because there was a steep decline in gasoline prices – <a href="https://fred.stlouisfed.org/series/CUSR0000SETB01">down 9.4% in the month of December</a> after dropping 2% in November.</p>
<p>While that’s good news, it’s a bit puzzling. AAA was <a href="https://newsroom.aaa.com/2022/12/nearly-113-million-people-will-travel-from-december-23-to-january-2/">expecting demand for gasoline to be very high</a> over the month, which usually happens in winter. This typically pushes prices up. My best guess is either demand wasn’t as strong as expected due to fears of a coming recession or there has been an easing on the supply constraints that has contributed to pushing the price of gas up.</p>
<p>An exception to this downward energy price trend was in energy services – that is, electricity and piped gas – where prices actually ticked up. The reason is largely due to the rising cost of doing business. Utility companies and pipeline services are suffering as a result of higher labor costs and are passing on the added cost to consumers through higher prices. The <a href="https://www.bls.gov/news.release/empsit.nr0.htm">latest jobs report</a> shows average hourly earnings rose 4.6% in December from a year earlier.</p>
<h2>Groceries</h2>
<p>Overall food inflation slowed in December, with the cost of groceries rising just 0.2% in the month – down from 0.5% in November.</p>
<p>But there is a lot of variation in the cost of grocery items. While the price of fruits and vegetables fell in December, the cost of eggs jumped by 11.1%. That’s due to an <a href="https://www.reuters.com/world/us/us-nears-record-poultry-deaths-bird-flu-virus-type-complicates-fight-2022-10-18">outbreak of bird flu</a> that could well last until into the summer.</p>
<p>In addition to that, farms are seeing the same wage pressures as other businesses, which are then passed on to consumers.</p>
<h2>Housing</h2>
<p>The cost of shelter, whether from renting or owning, <a href="https://fred.stlouisfed.org/series/CUSR0000SAH1#0">rose 0.8% in December</a> – the biggest one-month gain since the 1980s. </p>
<p>This is understandable given the <a href="https://theconversation.com/federal-reserve-just-hiked-interest-rates-for-the-7th-time-this-year-so-why-are-mortgage-rates-coming-down-195779">numerous interest rate hikes</a> during 2022. Rising interest rates means that taking out a home loan is more costly, which in turn pushes more people into renting. Added demand on rental properties in turn pushes the prices that landlords demand up. </p>
<p>When interest rates eventually drop, it should bring the overall cost of shelter down, as it would encourage more people to buy homes. But I’m not optimistic that rates will fall until 2024, so don’t expect any downward movement on shelter in the coming months.</p>
<h2>Hospital visits</h2>
<p>The cost of going to the hospital was another category that saw a big increase. Average prices for hospital and related services jumped 1.5% in December, the <a href="https://fred.stlouisfed.org/series/CUSR0000SEMD#0">biggest gain since 2015</a>. </p>
<p>Again, this is due to the rising cost of doing business – that is, <a href="https://www.bloomberg.com/news/articles/2023-01-12/us-hospitals-continue-to-cope-with-elevated-labor-costs-from-the-pandemic">upward pressure on wages</a> – coupled with still-high energy costs. </p>
<h2>Used cars and trucks</h2>
<p>Another category that helped the overall pace of inflation slow down is used cars and trucks. </p>
<p>After soaring throughout the initial phase of the COVID-19 pandemic, used car prices have been plunging in recent months. They fell 2.5% in December, <a href="https://fred.stlouisfed.org/series/CUUR0000SETA02#0">putting the annual decline at 8.8%</a>. The cost of new cars also dropped in December.</p><img src="https://counter.theconversation.com/content/197770/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Edouard Wemy does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A drop in gas prices helped tame inflation in December 2022. But grocery prices and housing costs continued to rise.Edouard Wemy, Assistant Professor of Economics, Clark UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1904472022-12-16T00:40:16Z2022-12-16T00:40:16ZCurious Kids: how are babies made?<figure><img src="https://images.theconversation.com/files/498841/original/file-20221205-26-5mon89.jpg?ixlib=rb-1.1.0&rect=131%2C23%2C5044%2C3088&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.pexels.com/photo/photo-of-new-born-baby-covered-with-blue-blanket-3617844/">Pexels/Laura Garcia</a></span></figcaption></figure><blockquote>
<p>How are babies made? Giaan, age 8</p>
</blockquote>
<p><a href="https://theconversation.com/au/topics/curious-kids-36782"><img src="https://images.theconversation.com/files/291898/original/file-20190911-190031-enlxbk.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=90&fit=crop&dpr=1" width="100%"></a></p>
<p>Thanks for your interesting question, Giaan! </p>
<p>Lots of kids your age wonder about how babies are made. It’s an important question because making babies allows the human species (and other animals) to continue.</p>
<h2>Knowing the body parts</h2>
<p>The first step in making a baby happens when a sperm from a man’s body joins with an egg from a woman’s body. </p>
<p>To understand how this happens, it is helpful to know the proper names for different body parts. These <a href="https://www.nationwidechildrens.org/family-resources-education/health-wellness-and-safety-resources/helping-hands/body-system-reproductive-female">pictures</a> <a href="https://www.nationwidechildrens.org/family-resources-education/health-wellness-and-safety-resources/helping-hands/body-system-reproductive-male">may help</a>.</p>
<p>When I say man, I’m referring to a person with a penis and testes (sometimes called testicles).</p>
<p>When I say woman, I’m referring to a person with a uterus (where the baby grows), vagina (the passage inside the vulva that leads to the uterus), and ovaries.</p>
<p>But sometimes, people are born with differences in these body parts. And sometimes these body parts don’t match how people think of themselves – as a man or woman or non-binary person.</p>
<h2>Where do the sperm and egg come from?</h2>
<p>Puberty is the time when your body begins to develop, and changes from child to adult, usually in later primary school and early high school years.</p>
<p>Sperm look a bit like tadpoles but are so small that you need a microscope to see them. They are made in the man’s testes and are released in a liquid called semen.</p>
<p>Once a boy goes through puberty, their testes can produce millions of sperm each day.</p>
<figure class="align-center ">
<img alt="Scientist looks through a microscope" src="https://images.theconversation.com/files/498897/original/file-20221205-12013-hevoyr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/498897/original/file-20221205-12013-hevoyr.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=438&fit=crop&dpr=1 600w, https://images.theconversation.com/files/498897/original/file-20221205-12013-hevoyr.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=438&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/498897/original/file-20221205-12013-hevoyr.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=438&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/498897/original/file-20221205-12013-hevoyr.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=550&fit=crop&dpr=1 754w, https://images.theconversation.com/files/498897/original/file-20221205-12013-hevoyr.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=550&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/498897/original/file-20221205-12013-hevoyr.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=550&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Sperm are so small you’d need a microscope to see them.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/woman-scientist-looking-through-microscope-laboratory-341424821">Shutterstock</a></span>
</figcaption>
</figure>
<p>Eggs are stored in the woman’s ovaries and after puberty there is usually one egg released per month. </p>
<p>An egg is just big enough to see – it’s about the size of a grain of sand (still pretty small!).</p>
<h2>How do the sperm and egg join?</h2>
<p>So how do the sperm and egg join to make a baby? This is called conception.</p>
<p>The most common way conception happens is when a woman and a man have sexual intercourse. This means that the man’s penis goes inside the woman’s vagina and semen squirts out. </p>
<p>Sperm come out of the penis and go up into the vagina and if one of the sperm connects with an egg, the two may combine to make a baby (actually, it’s called an embryo at this stage). </p>
<figure class="align-center ">
<img alt="Sexual reproduction graphic" src="https://images.theconversation.com/files/498869/original/file-20221205-17-4ytnw7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/498869/original/file-20221205-17-4ytnw7.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=331&fit=crop&dpr=1 600w, https://images.theconversation.com/files/498869/original/file-20221205-17-4ytnw7.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=331&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/498869/original/file-20221205-17-4ytnw7.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=331&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/498869/original/file-20221205-17-4ytnw7.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=416&fit=crop&dpr=1 754w, https://images.theconversation.com/files/498869/original/file-20221205-17-4ytnw7.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=416&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/498869/original/file-20221205-17-4ytnw7.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=416&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The sperm and egg combine to make an embryo, which grows into a baby.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/sexual-reproduction-stages-steps-levels-fertilization-1883185015">Shutterstock</a></span>
</figcaption>
</figure>
<p>The embryo makes its way to the uterus, where it will grow for the next nine months, until the baby is ready to be born.</p>
<h2>Babies can be conceived in other ways too</h2>
<p>Some families have two mums, and they may ask a man to provide sperm (called a sperm donor). The doctor places the sperm in the uterus of one of the mums.</p>
<p>There is also a process called IVF (in-vitro-fertilisation). For this, doctors take sperm from a man and an egg from a woman and combine them in a dish to form an embryo. </p>
<p>Then the embryo is put inside the woman’s uterus by the doctor and continues to grow there, just like other babies. </p>
<h2>OK, then what happens?</h2>
<p>After the egg and sperm join to make an embryo, the embryo attaches to the mother’s uterus. </p>
<p>An organ called the placenta forms to supply the growing baby with all the nutrition it needs. </p>
<figure class="align-center ">
<img alt="Fetus and placenta in a uterus" src="https://images.theconversation.com/files/498834/original/file-20221205-26-iuc4zp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/498834/original/file-20221205-26-iuc4zp.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=443&fit=crop&dpr=1 600w, https://images.theconversation.com/files/498834/original/file-20221205-26-iuc4zp.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=443&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/498834/original/file-20221205-26-iuc4zp.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=443&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/498834/original/file-20221205-26-iuc4zp.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=556&fit=crop&dpr=1 754w, https://images.theconversation.com/files/498834/original/file-20221205-26-iuc4zp.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=556&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/498834/original/file-20221205-26-iuc4zp.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=556&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The placenta, shown here on the right, feeds the baby while it’s in its mother’s uterus.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-vector/baby-womb-placenta-1093421162">Shutterstock</a></span>
</figcaption>
</figure>
<p>When the baby is ready to be born, the muscles of the mum’s uterus start to contract and push the baby out through the vagina. </p>
<p>Some babies can’t be safely pushed out through the vagina and are delivered by an operation where a doctor removes the baby through a cut below the mum’s belly button (called a caesarean or c-section). During the operation, the doctor gives the mum a special injection in her back to take the pain away.</p>
<h2>Have more questions? Kids often do</h2>
<p>Often kids have more questions to ask about some of the things discussed in this article. Some kids want to know a lot more and others maybe just a couple of things. </p>
<p>If you have more questions, then have a chat with mum, dad, or another trusted adult, such as a teacher. <a href="https://www.healthywa.wa.gov.au/%7E/media/HWA/Documents/Healthy-living/Sexual-health/talk-soon-talk-often.pdf">Here is</a> a good resource for them to look at if they are unsure about how much to explain.</p><img src="https://counter.theconversation.com/content/190447/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bianca Cannon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Lots of kids wonder about this. Here are some of the basics.Bianca Cannon, GP and Lecturer at Sydney Medical School, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1964402022-12-14T16:01:37Z2022-12-14T16:01:37ZA brief history of Yorkshire puddings – and why they technically shouldn’t feature in a traditional Christmas dinner<figure><img src="https://images.theconversation.com/files/500455/original/file-20221212-113658-4pofku.jpg?ixlib=rb-1.1.0&rect=107%2C44%2C5883%2C3952&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">shutterstock</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/christmas-holiday-table-setup-traditional-food-753371995">Maksym Poriechkin/Shutterstock</a></span></figcaption></figure><p>Christmas dinner is considered by many to be the best meal of the year and yet when it comes to deciding what this meal should consist of people’s opinions often differ. </p>
<p>For some there will never be a centre piece that can replace the turkey, although often there are additional meats included such as roast ham, beef or pork, alongside roast potatoes, Brussels sprouts, pigs in blankets, bread sauce and stuffing. And of course, there are those who are vegetarian or vegan and prefer a nut roast.</p>
<p>Then there’s the Yorkshire pudding. For some <a href="https://www.manchestereveningnews.co.uk/whats-on/food-drink-news/christmas-dinner-yorkshire-puddings-poll-17471470">a must-have</a> on Christmas day while for other more traditionalists it seems a Yorkshire pudding <a href="https://www.mirror.co.uk/news/weird-news/nation-divided-over-whether-yorkshire-25744035">should go nowhere near</a> a Christmas dinner.</p>
<p>To understand the origins of the Yorkshire pudding Christmas dinner debate we need to turn the clock back to the time when the original pudding was first created.</p>
<h2>The origin story</h2>
<p>Prior to being given the prefix of Yorkshire in 1747 in the <a href="https://www.amazon.co.uk/Art-Cookery-Made-Plain-Easy/dp/1557094624">bestselling cookbook</a> The Art of Cookery Made Plain and Simple by English cookery writer Hannah Glasse, a Yorkshire Pudding was simply known as a “batter” or “dripping pudding”. </p>
<p>The <a href="https://www.historic-uk.com/CultureUK/Yorkshire-Pudding/">original serving of the Yorkshire pudding</a> was as an appetiser to a main meal, usually with gravy. This was because it would fill you up, meaning you wouldn’t eat as much meat, which was expensive. It was originally cooked in northern England over a fire with the meat roasting above it. The fats and juices from the meat would drip into the pudding and provide flavour and colour.</p>
<p>Traditionally, the word “pudding” referred to homely and rustic desserts that were commonly eaten by the lower classes. These could be either sweet or salty. Pudding dishes are mainly made with flour and have a cake-like consistency. Other savoury puddings include – <a href="https://www.bbcgoodfood.com/recipes/steak-kidney-pudding">steak and kidney pudding</a> and <a href="https://www.bbc.co.uk/food/recipes/lamb_and_kidney_suet_94115">suet pudding</a>. </p>
<figure class="align-center ">
<img alt="Tray of Yorkshire Puddings" src="https://images.theconversation.com/files/500477/original/file-20221212-113221-9tmah6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500477/original/file-20221212-113221-9tmah6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=411&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500477/original/file-20221212-113221-9tmah6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=411&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500477/original/file-20221212-113221-9tmah6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=411&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500477/original/file-20221212-113221-9tmah6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=516&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500477/original/file-20221212-113221-9tmah6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=516&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500477/original/file-20221212-113221-9tmah6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=516&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">To Yorkshire or not?</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/beef-dripping-yorkshire-puddings-on-metal-486225895">Image Source Trading Ltd/Shutterstock</a></span>
</figcaption>
</figure>
<p>The Yorkshire Pudding is a baked pudding made from a batter of eggs, flour and milk or water. It has become a common British side dish which is versatile and can be served in many different ways – although mainly recognised as an accompaniment to a roast dinner. Yorkshire puddings were originally made by tipping the batter into the fat around the roasting meat, but progressed over the years to be given <a href="https://www.historic-uk.com/CultureUK/Yorkshire-Pudding/">their own square dish</a>. </p>
<p>The smaller circular puddings we are more familiar with today date back to Hannah Glasse’s original recipe, in which spoonfuls of batter were dropped into fat surrounding the meat – and often referred to as Yorkshire puffs. </p>
<p>It has been <a href="https://www.amazon.co.uk/History-Recipes-Sitwell-William-published/dp/B00EKYHX52">suggested</a> the pudding was given the name “Yorkshire” due to the <a href="https://www.telegraph.co.uk/foodanddrink/11041921/The-Kitchen-Thinker-the-history-of-Yorkshire-pudding.html">region’s association with coal</a> and the high temperatures this produced that helped to make crispy <a href="https://www.inverse.com/article/42912-hannah-glasse-yorkshire-puddings">batter</a>.</p>
<h2>Healthy or pure indulgence?</h2>
<p>When you look at the individual ingredients that make up a Yorkshire pudding they are <a href="https://www.behealthynow.co.uk/nutrition/is-yorkshire-pudding-good-or-bad-for-you/">quite healthy</a>. But the way they are cooked is another matter. </p>
<p>Eggs, for example, are considered one of the <a href="https://theconversation.com/eight-cracking-facts-about-eggs-150797">most nutritious foods on the planet</a> and contain protein, vitamin B2, B6, B12, zinc, iron and selenium. Milk is also nutrient rich in both protein and fat along with calcium. While flour can <a href="https://www.nutritionix.com/food/yorkshire-pudding">provide you with micronutrients</a>. For example one cup of flour includes one gram of thiamin (vitamin B1), which is 85% of your recommended daily intake. </p>
<p>Traditionally Yorkshire Puddings are cooked in fat or dripping. A small amount of fat is essential in our diets as it’s a source of essential fatty acids, which the body cannot make itself. But <a href="https://www.bhf.org.uk/informationsupport/heart-matters-magazine/nutrition/cooking-skills/healthy-roasts/healthy-roast-without-anyone-noticing">too much fat</a> can lead to weight gain. </p>
<p>Vegetable oils such as sunflower can also be used as they reach very high temperatures. There has also been debate as to whether olive oil can be used, however as long as it’s a <a href="https://www.realsimple.com/food-recipes/cooking-tips-techniques/olive-oil-smoke-point-myth">good quality</a>, true <a href="https://www.aboutoliveoil.org/olive-oil-smoke-point">olive oil</a> it’s fine. </p>
<h2>Recipes and ideas</h2>
<p>As well as being a roast dinner side dish, these <a href="https://www.bbcgoodfood.com/howto/guide/yorkshire-puddings">humble puddings</a> are ideal for a cheap and filling family supper. The batter can be turned into puffy pizza bases, fluffy wraps and impressive toad in the holes. </p>
<p>It would also appear that Yorkshire pudding style dishes are now eaten all over the world. <a href="https://foodanddrink.yorkshirepost.co.uk/food/12-things-you-dont-know-yorkshire-pudding/#:%7E:text=Japan%20has%20a%20version%20of,scraps%2C%20onion%20and%20pickled%20ginger.">Japan serves them</a> with anything from cheese to jam and with soup. <a href="https://rouxbe.com/recipes/3000-popovers-yorkshire-puddings">The popover</a> is the US version of the Yorkshire pudding, which dates back to 1850. While Germany and the Netherlands make <a href="https://www.bbcgoodfood.com/recipes/dutch-baby-pancake-drunken-cherries">Dutch Babies</a> which is a flat Yorkshire pudding with berries and sugar on top. </p>
<figure class="align-center ">
<img alt="Yorkshire pudding with cranberries and cream." src="https://images.theconversation.com/files/500480/original/file-20221212-116664-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500480/original/file-20221212-116664-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500480/original/file-20221212-116664-4pofku.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500480/original/file-20221212-116664-4pofku.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500480/original/file-20221212-116664-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500480/original/file-20221212-116664-4pofku.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500480/original/file-20221212-116664-4pofku.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Anyone for a sweet Yorkshire pud?</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/homemade-yorkshire-pudding-redcurrant-sauce-on-2193429247">Geshas/Shutterstock</a></span>
</figcaption>
</figure>
<p>Back to the original debate then – should we or should we not have a Yorkie with our Christmas Dinner? If you are a strict traditionalist, then technically you should steer clear. It’s unlikely that Yorkshire puddings were included in the first <a href="https://www.english-heritage.org.uk/christmas/christmas-dinners-through-history/">traditional Christmas dinners</a> because they had not yet been invented. Though it should also be noted that neither would one have expected to see <a href="https://www.bbcgoodfood.com/recipes/classic-pigs-blankets">pigs in blankets</a> on an early Christmas dinner plate. Despite often being considered a Christmas staple, they’ve only been around since the 1950s.</p>
<p>So I would say, why not include the Yorkshire pudding, food trends are always changing and modernising. Indeed, Christmas dinner <a href="https://inews.co.uk/inews-lifestyle/food-and-drink/christmas-dinner-traditional-history-why-eat-favourite-festive-recipes-1352886">dates back to medieval times</a> and has been evolving ever since.</p>
<p>You could even dress these puddings up for the Christmas table – <a href="https://www.masoncash.co.uk/recipe/christmas-yorkshire-pudding-canapes">Yorkshire Pudding canapes</a> anyone? While any left over batter could also be used to make a toad in the hole with turkey and gravy – or even topped with cranberries and ice cream – it is Christmas after all.</p><img src="https://counter.theconversation.com/content/196440/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hazel Flight does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>To understand the origins of the Yorkshire pudding Christmas dinner debate we need to turn the clock back to the time when the original pudding was first created.Hazel Flight, Programme Lead Nutrition and Health, Edge Hill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1952482022-11-30T16:25:44Z2022-11-30T16:25:44ZEgg shortage: a nutritionist on the best egg alternatives<figure><img src="https://images.theconversation.com/files/497954/original/file-20221129-20-lu28hp.jpg?ixlib=rb-1.1.0&rect=84%2C58%2C5523%2C3673&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Anyone for scrambled tofu?</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/tofu-scramble-vegetables-white-plate-vegan-1517848847">Shutterstock</a></span></figcaption></figure><p>Eggs are currently in short supply, with shops and supermarkets limiting their sales. The main cause of this shortage has been blamed on the avian (bird) flu which has <a href="https://www.farminguk.com/news/shoppers-met-with-empty-shelves-as-egg-shortage-begins-to-bite_61575.html">risen to a record number of cases</a>. However, egg producers are also reporting that the egg shortage is due to the unprecedented level of <a href="https://www.theguardian.com/business/2022/nov/17/uk-egg-shortages-to-last-beyond-christmas-industry-warns">inflation and spiralling costs</a> driven by <a href="https://www.feednavigator.com/Article/2022/08/01/uk-calls-continue-for-support-for-egg-producers-as-feed-costs-escalate">global events</a>. </p>
<p>Those following a vegan lifestyle and people who follow some religions, such as Hinduism and Jainism <a href="https://doi.org/10.1177/1478210318780553">do not eat eggs</a> as they are not viewed as strictly vegetarian. So there are already plenty of egg alternatives out there.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/eight-cracking-facts-about-eggs-150797">Eight cracking facts about eggs</a>
</strong>
</em>
</p>
<hr>
<p>When it comes to egg replacements, there does need to be some consideration as to whether the substitute has the <a href="https://www.eatright.org/food/nutrition/vegetarian-and-special-diets/egg-alternatives">same moisture, protein and fats</a> as an egg. It also needs to be able to support the other ingredients without overpowering them to maintain the taste. So what are the options?</p>
<h2>Pureed fruit</h2>
<p>As eggs are key in providing structure, leavening, richness, colour and flavour to baked products they are central to most recipes. But pureed fruits can be particularly good substitutes in baking cakes, muffins, brownies and quick breads. </p>
<figure class="align-center ">
<img alt="Mashed bananas in a bowl." src="https://images.theconversation.com/files/497984/original/file-20221129-18-n4pox3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/497984/original/file-20221129-18-n4pox3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/497984/original/file-20221129-18-n4pox3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/497984/original/file-20221129-18-n4pox3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/497984/original/file-20221129-18-n4pox3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/497984/original/file-20221129-18-n4pox3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/497984/original/file-20221129-18-n4pox3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Turn your old bananas into ‘eggs’.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-hand-mashing-several-bananas-bake-2002516169">Shutterstock</a></span>
</figcaption>
</figure>
<p>Fruits such as unsweetened apple sauce, banana, pumpkin and avocado are the most popular examples. Though some care needs to be taken if using bananas as they can have a distinct flavour within cooking. Fruits are an excellent source of essential vitamins and minerals as well as being <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6315720/">high in fibre</a>. They also include a wide range of <a href="https://www.webmd.com/diet/health-benefits-antioxidants#1">antioxidants</a> which can lower your odds of some diseases.</p>
<h2>Flaxseed and Chia seeds</h2>
<p><a href="https://doi.org/10.3390/nu11051171">Flaxseed</a> and <a href="https://www.hsph.harvard.edu/nutritionsource/food-features/chia-seeds/">Chia seeds</a> are <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6627181/">highly nutritious</a> egg alternatives – high in omega-3 fatty acids, fibre and other unique plant compounds, including high levels of antioxidants. </p>
<p>Flaxseed comes from the flowering flax plant, which originates from Egypt. Similarly, Chia seeds are the edible seeds of a flowering plant from the mint family. The plant originates from Central and South America. As an ingredient, the seeds are very versatile because they can absorb liquid and form a gel-like substance – making them a perfect egg replacement. </p>
<figure class="align-center ">
<img alt="Glass jar filled with pudding and topped with fruit." src="https://images.theconversation.com/files/497992/original/file-20221129-12-bytwwu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/497992/original/file-20221129-12-bytwwu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/497992/original/file-20221129-12-bytwwu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/497992/original/file-20221129-12-bytwwu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/497992/original/file-20221129-12-bytwwu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/497992/original/file-20221129-12-bytwwu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/497992/original/file-20221129-12-bytwwu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Chia pudding: mix chia seeds with a milk of your choice and a little honey to create a healthy dessert.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/chia-pudding-fresh-berries-glass-jar-1054685843">Shutterstock</a></span>
</figcaption>
</figure>
<p>The seeds of both can either be ground at home or bought as a ready-made seed meal. When mixed with water, the paste can then be used for making pancakes, waffles, muffins, breads and cookies. These seeds may have a slightly nutty flavour when used in recipes.</p>
<h2>Tofu</h2>
<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6250531/">Tofu</a> is an ideal egg substitute as it’s an excellent source of protein, vitamins and minerals including calcium, iron, manganese, zinc, selenium, phosphorous and B vitamins which can protect against illnesses such as heart disease, diabetes and some cancers. It also promotes brain and bone health.</p>
<figure class="align-center ">
<img alt="Quiche on a chopping board" src="https://images.theconversation.com/files/498001/original/file-20221129-26-liecfx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/498001/original/file-20221129-26-liecfx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/498001/original/file-20221129-26-liecfx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/498001/original/file-20221129-26-liecfx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/498001/original/file-20221129-26-liecfx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/498001/original/file-20221129-26-liecfx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/498001/original/file-20221129-26-liecfx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">You can use tofu to make both quiches and cheesecakes.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/homemade-cake-short-bark-beetroot-tofu-688227955">Shutterstock</a></span>
</figcaption>
</figure>
<p>Silken tofu is a relatively flavourless food with a high-water content leading to a softer consistency in baking. While <a href="https://www.theguardian.com/food/2022/nov/08/plant-based-chefs-share-eggcellent-vegan-alternatives-amid-avian-flu">scrambled tofu</a> is an excellent substitute for those who want to still feel they are eating eggs on their own.</p>
<h2>Aquafaba</h2>
<p><a href="https://doi.org/10.3791%2F56305">Aquafaba</a> is the liquid left over from cooked chickpeas and is an ideal substitute for binding. It can also be whipped into stiff peaks and used to make meringues, macaroons, waffles and mayonnaise. </p>
<p>Although you would only use the liquid for the egg substitute do not throw the chickpeas away as these are a rich source of protein, vitamins, minerals and fibre. </p>
<figure class="align-center ">
<img alt="Meringues and chickpeas." src="https://images.theconversation.com/files/497998/original/file-20221129-18-ip9v6t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/497998/original/file-20221129-18-ip9v6t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=411&fit=crop&dpr=1 600w, https://images.theconversation.com/files/497998/original/file-20221129-18-ip9v6t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=411&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/497998/original/file-20221129-18-ip9v6t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=411&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/497998/original/file-20221129-18-ip9v6t.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=516&fit=crop&dpr=1 754w, https://images.theconversation.com/files/497998/original/file-20221129-18-ip9v6t.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=516&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/497998/original/file-20221129-18-ip9v6t.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=516&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Make meringue the vegan way.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/vegan-cooking-concept-meringue-canned-chickpea-1962659422">Shutterstock</a></span>
</figcaption>
</figure>
<h2>Final tips</h2>
<p>You could also try vinegar and baking soda, when mixed together they create a chemical reaction producing carbon dioxide and water. This added instead of an egg can work especially well in baked goods that are meant to be light and airy such as cakes and quick breads.</p>
<p>Both yoghurt and buttermilk are also good substitutes for eggs, but again use plain versions to avoid flavouring your cooking. These work well in muffins and cakes. You could also use chickpea flour and water to create pancakes, quiches and in baking.</p>
<p>As Christmas is fast approaching and festive baking needs to be completed an alternative to those all-important eggs needs to be considered. So don’t despair if you can’t get your hands on any as there are plenty of options. But you may want to experiment first with the various substitutes to find what works best with your recipes.</p><img src="https://counter.theconversation.com/content/195248/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Hazel Flight does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Eggs are hard to beat, but there are plenty of other options.Hazel Flight, Programme Lead Nutrition and Health, Edge Hill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1939952022-11-14T13:28:19Z2022-11-14T13:28:19ZBird flu has made a comeback, driving up prices for holiday turkeys<figure><img src="https://images.theconversation.com/files/493636/original/file-20221105-11-s3rd8v.jpg?ixlib=rb-1.1.0&rect=16%2C4%2C2766%2C1785&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Healthy turkeys on a farm in West Newfield, Maine.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/turkey-eye-a-photographer-from-their-side-of-the-fence-news-photo/1237706083">Shawn Patrick Ouellette/Portland Press Herald via Getty Images</a></span></figcaption></figure><p><em>An <a href="https://www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/avian/avian-influenza/hpai-2022/2022-hpai-commercial-backyard-flocks">outbreak of highly pathogenic avian influenza</a> has spread through chicken and turkey flocks in 46 states since it was first detected in Indiana on Feb. 8, 2022. The outbreak is also taking a heavy toll in <a href="https://www.ctvnews.ca/canada/bird-flu-cases-on-the-rise-what-this-means-for-poultry-and-egg-prices-1.6095332">Canada</a> and <a href="https://www.ecdc.europa.eu/en/news-events/2021-2022-data-show-largest-avian-flu-epidemic-europe-ever">Europe</a>.</em> </p>
<p><em>Better known as bird flu, avian influenza is a family of highly contagious viruses that are not typically harmful to most wild birds that transmit it, but are deadly to domesticated birds. The virus spreads quickly through poultry flocks and almost always causes severe disease or death, so when it is detected, officials quarantine the site and cull all the birds in the infected flock.</em> </p>
<p><em>As of early November, this outbreak had led to the culling of over 50 million birds from Maine to Oregon, driving up prices for eggs and poultry – <a href="https://www.axios.com/2022/11/02/turkey-shortage-thanksgiving-2022">including holiday turkeys</a>. This matches the toll from a <a href="https://www.ers.usda.gov/publications/pub-details/?pubid=86281">2014-2015 bird flu outbreak</a> that previously was considered the most significant animal disease event in U.S. history. <a href="https://scholar.google.com/citations?user=lLdLWigAAAAJ&hl=en">Yuko Sato</a>, an associate professor of veterinary medicine who works with poultry producers, explains why so many birds are getting sick and whether the outbreak threatens human health.</em></p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1590030204226785280"}"></div></p>
<h2>Why is avian influenza so deadly for domesticated birds but not for wild birds that carry it?</h2>
<p>Avian influenza (AI) is a contagious virus that affects all birds. There are two groups of aviain influenza viruses that cause disease in chickens: highly pathogenic AI (HPAI) and low pathogenic AI (LPAI). </p>
<p>HPAI viruses cause high mortality in poultry, and occasionally in some wild birds. LPAI can cause mild to moderate disease in poultry, and usually little to no clinical signs of illness in wild birds. </p>
<p>The primary <a href="https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section10.html">natural hosts and reservoir</a> of AI viruses are wild waterfowl, such as ducks and geese. This means that the virus is well adapted to them, and these birds do not typically get sick when they are infected with it. </p>
<p>But when domesticated poultry, such as chickens and turkeys, come in direct or indirect contact with feces of infected wild birds, they become infected and start to show symptoms, such as <a href="https://www.cdc.gov/flu/avianflu/hpai/hpai-background-clinical-illness.htm">lethargy, coughing and sneezing and sudden death</a>. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of US and Canada showing avian influenza distribution among commercial, backyard and wild bird flocks." src="https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=464&fit=crop&dpr=1 600w, https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=464&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=464&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=583&fit=crop&dpr=1 754w, https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=583&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/493635/original/file-20221105-15-ciub47.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=583&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Migrating wild birds, most of which are not harmed by avian influenza, are known to spread the disease to commercial and backyard flocks.</span>
<span class="attribution"><a class="source" href="https://www.usgs.gov/media/images/distribution-highly-pathogenic-avian-influenza-h5-and-h5n1-north-america-20212022">USGS</a></span>
</figcaption>
</figure>
<h2>There are multiple strains of avian influenza. What type is this outbreak, and is it dangerous to humans?</h2>
<p>The virus of concern in this outbreak is a Eurasian H5N1 HPAI virus that causes high mortality and severe clinical signs in domesticated poultry. Scientists who <a href="https://www.usgs.gov/centers/nwhc/science/avian-influenza-surveillance">monitor wild bird flocks</a> have also detected a <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/genetic-reassortment">reassortant virus</a> that contains genes from both the Eurasian H5 and low pathogenic North American viruses. Reassortment happens when multiple strains of the virus circulating in the bird population exchange genes to create a new strain of the virus, much as new strains of COVID-19 like omicron and delta have emerged during the ongoing pandemic.</p>
<p>According to the U.S. Centers for Disease Control and Prevention, <a href="https://www.cdc.gov/flu/avianflu/spotlights/2021-2022/h5n1-low-risk-public.htm">the risk to public health from this outbreak is low</a>. No human illnesses were associated with the <a href="https://www.cdc.gov/flu/avianflu/spotlights/2015/update-h5-outbreak-birds.htm">2014-2015 H5N1 outbreak in the U.S.</a></p>
<p>The only known human case in the U.S. during the current outbreak was found in a man in Colorado who <a href="https://www.cdc.gov/media/releases/2022/s0428-avian-flu.html">had contact with infected birds</a>. The man tested positive once, then negative on follow-up tests, and reported only mild symptoms, so health experts theorized that the virus may have been present in his nose <a href="https://www.statnews.com/2022/04/29/10-people-under-watch-after-bird-flu-detected-in-man/">without actually causing an infection</a>. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/acK6c8BTtv4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Health officials recommend avoiding direct contact with wild birds to avoid spreading avian flu.</span></figcaption>
</figure>
<h2>Are these outbreaks connected to wild bird migration?</h2>
<p>Yes, wild bird migration has been an important factor in this outbreak. Scientists have detected the same H5N1 virus that is infecting poultry in <a href="https://www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/avian/avian-influenza/hpai-2022/2022-hpai-wild-birds">more than 3,000 wild birds</a> during this outbreak, compared with 75 detections during the 2014-2015 outbreak. This tells us that the virus is highly prevalent in wild bird populations. </p>
<p>While most detections occur in ducks and geese, the virus has also been found in other bird species, including raptors, such as eagles and vultures, and other waterfowl, such as swans and <a href="https://www.mycouriertribune.com/outdoors/pelican-found-in-county-with-bird-flu">pelicans</a>. Birds of prey are among the most susceptible: As of early November 2022, wildlife agencies had <a href="https://www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/avian/avian-influenza/hpai-2022/2022-hpai-wild-birds">reported</a> more than 300 bird flu deaths in black vultures, over 200 deaths in bald eagles and more than 100 each in great horned owls and red-tailed hawks.</p>
<p>The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service conducts targeted sampling to test wild birds in fall and early winter, which <a href="https://birdcast.info/migration-tools/live-migration-maps/">correlates with migration season</a>. This helps scientists and wildlife managers understand where avian flu viruses may be introduced to domestic flocks, track their spread and monitor for any reassortment.</p>
<p>Because there are high amounts of virus circulating, wildlife agencies advise against <a href="https://wildlife.utah.gov/avian-influenza.html">handling or eating game birds that appear sick</a>. Waterfowl can also be infected, with no signs of illness, so hunters need to be especially careful not to handle or eat game birds without properly cleaning their clothing and equipment afterward and ensuring the birds are cooked to an <a href="https://wildlife.ca.gov/News/avian-influenza-guidance-for-waterfowl-hunters">internal temperature of 165 degrees F (74 C)</a> before consuming them.</p>
<p>Hunters and other members of the public are advised not to approach any wild animals that are acting strange and to report any such sightings to officials. In some cases, avian flu viruses have spilled over to other wild animals, such as <a href="https://doi.org/10.3201/eid2711.211281">red foxes</a>, <a href="https://wdfw.medium.com/avian-influenza-common-questions-and-answers-regarding-transmission-to-mammals-b70a73d53a66">raccoons</a>, <a href="https://www.nytimes.com/2022/06/18/health/avian-flu-h5n1-foxes.html">skunks, opossums and bobcats</a>. We did not see this trend in 2014-15.</p>
<p><div data-react-class="Tweet" data-react-props="{"tweetId":"1587164183547838470"}"></div></p>
<p>HPAI is a transboundary disease, which means it is highly contagious and spreads rapidly across national borders. Some research indicates that detection of HPAI viruses in wild birds <a href="https://doi.org/10.1002/jwmg.22171">has become more common</a>. </p>
<p>Detection of HPAI in wild birds is seasonal, with a peak in February and a low point in September. Many migratory bird species <a href="https://www.usgs.gov/centers/nwhc/science/avian-influenza">travel thousands of miles between continents</a>, posing a continuing risk of AI virus transmission.</p>
<p>On the positive side, we have better diagnostic tests for much more rapid and improved detection of avian influenza compared to 20 to 30 years ago, and can use molecular diagnostics such as <a href="https://www.webmd.com/lung/coronavirus-glossary#1">polymerase chain reaction (PCR) tests</a> – the same method labs use to detect COVID-19 infections. </p>
<h2>How are poultry farmers affected when HPAI is detected in their flocks?</h2>
<p>To detect AI, the U.S. Department of Agriculture oversees routine testing of flocks by farmers and carries out federal inspection programs to ensure that eggs and birds are safe and free of virus. When H5N1 is diagnosed on a farm or in a backyard flock, state and federal officials will quarantine the site and cull and dispose of all the birds in the infected flock. Then the site is cleaned and decontaminated, a process that includes removing organic materials like manure and chicken feed that can <a href="https://extension.psu.edu/creating-a-farm-plan-for-highly-pathogenic-avian-influenza">harbor virus particles</a>. </p>
<p>After <a href="https://www.aphis.usda.gov/publications/animal_health/pos-hpai-stop-avian-influenza-outbreaks.508.pdf">several weeks</a> without new virus detections, the area is required to test negative in order to be deemed free of infection. We call this process the four D’s of outbreak control: diagnosis, depopulation, disposal and decontamination.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Wire cages hold chicken figurines" src="https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Live birds are banned at agricultural fairs during bird flu outbreaks to avoid spreading infections. These fake chickens were on display at the Cabarrus County, N.C., fair in 2015, a previous H5N1 outbreak year.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/real-birds-banned-at-state-fairs-due-to-bird-flu-these-are-news-photo/582537669">Elizabeth W. Kearley via Getty Images</a></span>
</figcaption>
</figure>
<p>Flock owners are eligible for federal <a href="https://www.aphis.usda.gov/publications/animal_health/fs-hpai-indemnity-and-compensation.508.pdf">indemnity payments</a> for birds and eggs that have to be destroyed because of avian influenza, as well as for the costs of removing birds and cleaning and disinfecting their farms. This support is designed to help producers move past an outbreak, get their farms back in condition for restocking and get back into business as soon as possible. </p>
<p>But these payments <a href="https://www.fcsamerica.com/resources/education/common-ground/common-ground/2022/05/24/financial-best-practices-in-the-face-of-avian-influenza">almost never cover all of farmers’ expenses</a>. Poultry farms can’t always recover financially from major bird flu outbreaks. That makes it especially important to focus on <a href="http://extension.msstate.edu/publications/information-sheets/biosecurity-measures-combat-avian-influenza-threat">prevention strategies</a> to keep the virus out. </p>
<p><em>This article has been updated to reflect reported avian influenza deaths in birds of prey.</em></p>
<p><em>This is an updated version of an <a href="https://theconversation.com/bird-flu-is-killing-millions-of-chickens-and-turkeys-across-the-us-180299">article</a> originally published on April 7, 2022.</em></p><img src="https://counter.theconversation.com/content/193995/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Yuko Sato receives funding from the US Department of Agriculture, the Bill and Melinda Gates Foundation, allied industry companies, the Pew Foundation, the Egg Industry Center, the US Poultry & Egg Association, and internally through Iowa State University. She is affiliated with the Iowa Poultry Association, the Iowa Turkey Federation, United Egg Producers and the US Animal Health Association. </span></em></p>Hunters are warned to take precautions handling wild birds, and the virus can spill over to non-avian species, so no one should approach wild animals that appear ill.Yuko Sato, Associate Professor of Veterinary Medicine, Iowa State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1878932022-10-04T12:25:06Z2022-10-04T12:25:06ZSupreme Court grapples with animal welfare in a challenge to a California law requiring pork to be humanely raised<figure><img src="https://images.theconversation.com/files/486884/original/file-20220927-14-49sf36.jpg?ixlib=rb-1.1.0&rect=26%2C5%2C3557%2C2364&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Pig farming may evoke images like this, but the reality for most commercial pork production is very different.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/different-coloured-piglets-looking-into-the-camera-royalty-free-image/1055964804">linephoto via Getty Images</a></span></figcaption></figure><p>Should Californians be able to require higher welfare standards for farm animals that are raised in other states if products from those animals are to be sold in California? The U.S. Supreme Court will confront that question when it hears oral argument in <a href="https://www.oyez.org/cases/2022/21-468">National Pork Producers Council v. Ross</a> on Oct. 11, 2022.</p>
<p>Pork producers are challenging a law that California voters <a href="https://ballotpedia.org/California_Proposition_12,_Farm_Animal_Confinement_Initiative_(2018)">adopted in 2018</a> via ballot initiative with over 63% approval. It set new conditions for raising hogs, veal calves and egg-laying chickens, whose meat or eggs are sold in California. The state represents <a href="https://nppc.org/ca-prop-12/">about 15% of the U.S. pork market</a>. </p>
<p>At most commercial hog farms, pregnant sows are kept in “gestation crates” that measure 2 feet by 7 feet – enough room for the animals to <a href="http://animalwelfare.ucdavis.edu/uploads/6/3/7/0/63703691/prop_12_faq_swine.pdf">sit, stand and lie down, but not enough to turn around</a>. California’s law requires that each sow must have <a href="https://law.justia.com/codes/california/2010/hsc/25990-25994.html#:%7E:text=25990.,(b)%20Turning%20around%20freely.">at least 24 square feet of floor space</a> – nearly double the amount that most now get. It does not require farmers to raise free-range pigs, just to provide more square feet when they keep hogs in buildings. </p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/I_rCRgCcjW8?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Pork farmers say gestation crates keep pregnant sows from fighting, but animal welfare advocates call the devices inhumane.</span></figcaption>
</figure>
<p>The <a href="https://nppc.org/">National Pork Producers Council</a> argues that this requirement <a href="https://nppc.org/ca-prop-12/">imposes heavy compliance costs</a> on farmers across the U.S., since large hog farms may house <a href="https://www.nationalhogfarmer.com/reproduction/does-farm-size-matter-swine-production">thousands of sows</a> and that it restricts interstate commerce. The Constitution’s commerce clause <a href="https://www.law.cornell.edu/wex/commerce_clause">delegates authority to regulate interstate commerce to the federal government</a>. In a series of cases over the past 50 years, the Supreme Court has made clear that it will strike down any state law that seeks to <a href="https://www.oyez.org/cases/2006/05-1345">control commerce in another state or give preference to in-state commerce</a>. </p>
<p>Farmers and animal welfare advocates understand that if California wins, states with the most progressive animal welfare policies – primarily West Coast and Northeast states – will be able to effectively set national standards for the well-being of many agricultural animals, including chickens, dairy and cattle. Conceivably, California might also be able to require basic conditions for human labor, such as minimum wage standards, associated with products sold in California.</p>
<p><a href="https://www.ers.usda.gov/data-products/chart-gallery/gallery/chart-detail/?chartId=103505">Nine other states</a> have already adopted laws requiring pork producers to phase out gestation crates. Massachusetts’s law would also apply to retail sales of pork raised elsewhere, like California’s, but <a href="https://www.foodqualityandsafety.com/article/court-orders-delay-of-massachusetts-pork-production-law/">its enforcement is on hold</a> pending the Supreme Court’s ruling in the California case.</p>
<h2>States control farm animal welfare</h2>
<p>The main federal law that regulates living conditions for animals is the <a href="https://www.nal.usda.gov/animal-health-and-welfare/animal-welfare-act">Animal Welfare Act</a>, which was signed into law in 1966. Among other things, it requires the Department of Agriculture to adopt humane regulations for the keeping of animals that are exhibited in zoos and circuses or sold as pets. However, farm animals are <a href="https://www.aphis.usda.gov/aphis/ourfocus/animalwelfare/sa_awa">explicitly exempted from the definition of “animal</a>.” </p>
<p>While the federal government is mute on farm animal welfare, each state clearly has the power to regulate this issue within its borders. For example, in recent years, nine states have <a href="https://blog.humanesociety.org/2021/06/breaking-nevada-becomes-ninth-state-to-ban-cages-for-egg-laying-hens.html">outlawed housing egg-laying chickens in “battery cages</a>” that have been the industry standard for decades. These wire enclosures are so small that <a href="https://archive.nytimes.com/www.nytimes.com/interactive/2010/08/15/weekinreview/15marsh-grfk.html">the birds cannot spread their wings</a>. </p>
<p>Since many states still permit battery cages, egg-laying chickens’ quality of life depends on the state in which they reside. </p>
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<a href="https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Shelves lined with small wire cages, each holding multiple chickens." src="https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=407&fit=crop&dpr=1 600w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=407&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=407&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=511&fit=crop&dpr=1 754w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=511&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/486883/original/file-20220927-12-nldpmb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=511&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Chickens in battery cages on an Iowa poultry farm.</span>
<span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/ChinaChickenTrade/d5d0a3185fab492b8d39486d57e0ed4a/photo">AP Photo/Charlie Neibergall</a></span>
</figcaption>
</figure>
<p>It is also clear that the state of California has no power to adopt laws that are binding on the farmers of other states. This case falls between those two points – here’s how:</p>
<h2>California’s market power</h2>
<p>The California law says that if producers want to sell pork in California, they must raise pigs under conditions that comply with the state’s regulations. Farmers do not have to meet these standards unless they want to sell in California. The same requirement is applied to producers located in California and those based elsewhere, so the law does not directly discriminate between states in a way that would constitute a clear commerce clause violation.</p>
<p>Producers of <a href="https://www.poultryworld.net/poultry/cage-free-us-egg-industry-sooner-rather-than-later/">eggs</a> and <a href="https://www.agupdate.com/missourifarmertoday/news/livestock/builder-sees-producers-adapting-to-prop-12/article_f2c43598-ed80-11ec-a8bc-af01d15c519d.html">veal</a> who sell in California are on track to implement new space requirements for their animals under the law. In my view, however, much of the pork industry appears to be in denial. Instead of working out how to comply, the National Pork Producers Council wants the courts to set the California law aside.</p>
<p>Even as this case moves forward, however, major producers including <a href="https://www.hormelfoods.com/newsroom/news/hormel-foods-company-information-about-california-proposition-12/">Hormel</a> and <a href="https://s22.q4cdn.com/104708849/files/doc_financials/2021/q3/08-11-21_Tyson-Foods-080921.pdf">Tyson</a> have said they will be able to comply with the California standard. Niman Ranch, a network of family farmers and ranchers who raise livestock humanely and sustainably, has <a href="https://www.supremecourt.gov/DocketPDF/21/21-468/233498/20220815141539359_21-468_Amicus%20Brief.pdf">filed an amicus brief with the Supreme Court supporting California</a>.</p>
<p>Admittedly, pork farmers have invested millions of dollars in their existing facilities, and the system efficiently produces <a href="https://www.ers.usda.gov/topics/animal-products/hogs-pork/sector-at-a-glance/">huge quantities of cheap pork</a>. But Californians have taken the position that this output comes at an ethically unacceptable cost to animals in the system. </p>
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<h2>Weighing ethics against compliance costs</h2>
<p>In considering this case, the Supreme Court will confront two questions. First, does California’s requirement constitute a burden on interstate commerce? A U.S. District Court in California held that <a href="https://www.oyez.org/cases/2022/21-468">the answer was no</a>, and the U.S. 9th Circuit Court of Appeals affirmed this ruling. </p>
<p>There is no magical formula for what constitutes a burden on interstate commerce, so it is impossible to know in advance what the Supreme Court will say about this point of the case. The present court has not addressed this issue.</p>
<p>If the court should decide that the California law does restrict interstate commerce, it then must consider whether the measure meets the “Pike test,” which was set forth in the 1970 ruling <a href="https://www.oyez.org/cases/1969/301">Pike v. Bruce Church, Inc.</a>. In this case, the court held that a state law that “regulates even-handedly” must be upheld unless the burden that the law imposes on interstate commerce “is clearly excessive in relation to the putative local benefits.” Put another way, is Californians’ social interest in better welfare for pigs substantially outweighed by the economic cost to producers? </p>
<p>In another 2010 ruling, <a href="https://www.oyez.org/cases/2009/08-769">United States v. Stevens</a>, the court acknowledged that “the prohibition of animal cruelty itself has a long history in American law, starting with the early settlement of the Colonies.” However, the court concluded that depictions of animal cruelty – the plaintiff had been convicted for producing and distributing dogfighting videos – qualified as protected speech under the First Amendment and that this protection outweighed society’s interest in promoting animal welfare.</p>
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<figcaption><span class="caption">This video from the Rodale Institute, a nonprofit that conducts research, training and consumer education on organic agriculture, compares raising pigs on pasture to the large-scale confined model that dominates the pork industry.</span></figcaption>
</figure>
<h2>Is a national standard in the cards?</h2>
<p>Many animal welfare questions involve striking this kind of balance between ethical positions and economic consequences in a political context. It is like mixing oil and water, which makes predictions difficult. </p>
<p>The biggest unknown is what views the newest Supreme Court justices will bring to this case. Only four current justices – John Roberts, Clarence Thomas, Samuel Alito and Sonia Sotomayor – were members of the court when it ruled on the Stevens case in 2010. Will today’s court support California’s right to regulate products sold within its borders, or meat corporations’ economic arguments? How many justices will see farm animal welfare as an important public concern? </p>
<p>I expect that the court will uphold the California law – and that if this happens, within five years livestock producers will be proposing national legislation setting uniform welfare standards for farm animals. It is impossible to predict now whether a national law would improve animal welfare or adopt existing poor welfare practices.</p><img src="https://counter.theconversation.com/content/187893/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David Favre does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Pork producers are challenging a California law that animal welfare advocates call the most important measure for farm animal protection in decades.David Favre, Professor of Law at Michigan State University College of Law, Michigan State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1884332022-08-10T06:49:15Z2022-08-10T06:49:15ZWhat’s causing Australia’s egg shortage? A shift to free-range and short winter days<figure><img src="https://images.theconversation.com/files/478437/original/file-20220810-13-j2s91z.jpg?ixlib=rb-1.1.0&rect=0%2C822%2C5032%2C2527&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Klaus Nielsen/Pexels </span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Australia is experiencing a national egg shortage. Prices are rising and supermarket stocks are patchy. Some cafes are reportedly serving breakfast with <a href="https://www.smh.com.au/business/consumer-affairs/menu-tweaks-and-price-leaps-how-the-egg-shortage-threatens-your-sunday-brunch-20220804-p5b78y.html">one egg instead of two</a>. Supermarket giant Coles has reverted to COVID-19 conditions with a <a href="https://www.canstarblue.com.au/groceries/supermarkets-egg-shortage/">two-carton</a> limit. </p>
<p>We became used to grocery shortages throughout the lockdowns of 2020 and 2021. These were due to changes in buying patterns, stockpiling and panic-buying. Eggs were <a href="https://www.9news.com.au/national/egg-supermarket-supplies-strong-coronavirus-panic-shopping-concern/62f6e869-2099-4caf-a753-d51f0c5aa825">temporarily part of this</a>, along with flour, as people at home got baking. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-flour-is-still-missing-from-supermarket-shelves-137263">Why flour is still missing from supermarket shelves</a>
</strong>
</em>
</p>
<hr>
<p>But with lockdowns long past, what’s causing this egg shortage now? </p>
<p>News reports have quoted eggs producers blaming, at least in part, pandemic restrictions – because they reduced their laying flocks due to lower demand from restaurants and cafes. </p>
<p>That was the case in countries such as India, where <a href="https://www.rvo.nl/sites/default/files/2020/09/Poultry-sector-in-India-after-Covid-19.pdf">misinformation about poultry</a> being a source of COVID-19 led to a sharp decline in demand. But in Australia, an initial <a href="https://www.abc.net.au/news/rural/2020-10-09/egg-producers-dodge-a-bullet-during-coronavirus-pandemic/12739628">30% drop from hospitality</a> was compensated by a growth in retail sales.</p>
<p>What changed during that time was the way people got their eggs. Food delivery, food boxes and home cooking exploded for a time.</p>
<p>More fundamentally, this shortage reflects a long-term trend in egg-buying preferences, with a shift to free-range eggs, whose production is more affected by the colder, shorter days of winter.</p>
<h2>Shifting to free-range eggs</h2>
<p>Australians consume about <a href="https://www.australianeggs.org.au/egg-industry">17 million eggs</a> every day. In the 2020-21 financial year, egg farmers produced about 6.3 billion eggs. Of those, 52% were free-range. This compares to about 38% a decade ago. </p>
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<p><iframe id="LkkeZ" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/LkkeZ/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<hr>
<p>This growth, however, has not been consistent. Between 2012 and 2017, free-range eggs’ share of the market <a href="https://www.researchgate.net/publication/282909043_Free-range_egg_production_in_Australia_-_industry_trends_and_challenges">grew</a> about 10 percentage points, to about 48%. Growth in the past five years has been half that. </p>
<p>But with more rapid growth predicted, and the promise of higher profits, many egg farmers invested heavily in increasing free-range production. In New South Wales, for example, total flock size <a href="https://www.dpi.nsw.gov.au/about-us/publications/pdi/2021/eggs">peaked in 2017-18</a>. </p>
<p>Like many agricultural industries where farmers respond to price signals and predictions, this led to overproduction, leading to lower prices and profits. This in turn led to a <a href="https://www.dpi.nsw.gov.au/about-us/publications/pdi/2021/eggs">10% drop</a> in egg production the next year. </p>
<p>Compliance costs also increased. In 2018 the Australian Competition and Consumer Commission <a href="https://www.accc.gov.au/publications/a-guide-for-egg-producers">introduced rules</a> to police the marketing of eggs as “free-range”. </p>
<p>These rules mean hens need to have “meaningful and regular access” to an outdoor range during the daylight hours of their laying cycle (with a maximum density of 10,000 hens per hectare).</p>
<figure class="align-center ">
<img alt="Australia's consumer watchdog introduced free-range egg standards in 2018." src="https://images.theconversation.com/files/478477/original/file-20220810-22-odp1vv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/478477/original/file-20220810-22-odp1vv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/478477/original/file-20220810-22-odp1vv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/478477/original/file-20220810-22-odp1vv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/478477/original/file-20220810-22-odp1vv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/478477/original/file-20220810-22-odp1vv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/478477/original/file-20220810-22-odp1vv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Australia’s consumer watchdog introduced free-range egg standards in 2018.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>This experience has likely influenced farmers’ reticence to increase their flocks based on predictions of higher demand.</p>
<h2>Winter affects free-range production</h2>
<p>Producing free-range eggs is more expensive not just because it requires more land. Free-range hens are less consistent layers. </p>
<p>Hens kept in cages or barns are more regular producers because conditions are optimised to stimulate laying. Temperatures are constant, and hens are exposed to 16 hours of light every day. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=384&fit=crop&dpr=1 600w, https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=384&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=384&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=483&fit=crop&dpr=1 754w, https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=483&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/478440/original/file-20220810-17-qbvymn.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=483&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Hens kept in cages or barns are more regular producers.</span>
<span class="attribution"><span class="source">Yves Logghe/AP</span></span>
</figcaption>
</figure>
<p>Free-range hens are affected by hot or cold temperatures, wind and rain, and length of daylight. In winter months they have less energy and produce (on average) <a href="https://www.theguardian.com/australia-news/2022/aug/02/egg-shortage-hits-australia-as-supermarket-shelves-go-empty">20% fewer eggs</a> than a chicken confined indoors in controlled conditions. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/national-plan-to-allow-battery-cages-until-2036-favours-cheap-eggs-over-animal-welfare-163552">National plan to allow battery cages until 2036 favours cheap eggs over animal welfare</a>
</strong>
</em>
</p>
<hr>
<h2>Pressures on farmers</h2>
<p>The egg industry is flexible and adaptable – but the confluence of economic and environmental events in 2022 has made things difficult. Farmers will want to meet demand, but face time lags and cost pressures. </p>
<p>Increasing a laying flock takes about four months. An egg takes about three weeks to hatch. Under ideal conditions, chicks need another 17 weeks before they are ready to begin laying. </p>
<p>Any farmer who has begun this process in the past month will be producing more eggs by December. But then it will be summer, when they won’t need 20% more hens to make up for their winter slump.</p>
<p>Feed costs, which typically represent <a href="https://www.dpi.nsw.gov.au/about-us/publications/pdi/2021/eggs">60-70%</a> of layer production costs, have been increasing along with transport, electricity and interest rates. </p>
<p>So farmers must be cautious if they are to stay in business. It is preferable to undersupply than go bankrupt through oversupply.</p>
<p>Are farmers willing to invest in increasing production in an uncertain economic environment, with interest rates and costs going up and a recession on the horizon? Probably not. </p>
<p>So a short-term fix seems unlikely. Weather forecasts are not favourable. The Bureau of Meterology expects a <a href="http://www.bom.gov.au/climate/ahead/outlooks/">wetter August to October</a>, with “more than double the normal chance of unusually high rainfall”. That means less daylight and more cold. Blame the negative Indian Ocean dipole, not the chickens.</p>
<p>Come spring, with longer days and milder temperatures, along with an agricultural visa program, things should return to “normal”.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/eight-cracking-facts-about-eggs-150797">Eight cracking facts about eggs</a>
</strong>
</em>
</p>
<hr>
<p>Unless consumers are willing to pay more to ensure a constant supply in winter months, our shift to free-range eggs carries a higher likelihood of winter shortages.</p>
<p>We must do what we have done through every disruption in recent times: endure, adapt and prepare for the next crisis.</p><img src="https://counter.theconversation.com/content/188433/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Flavio Macau is affiliated with the Australasian Supply Chain Institute (ASCI)</span></em></p>Our shift to free-range eggs carries a higher likelihood of winter shortages.Flavio Macau, Associate Dean - School of Business and Law, Edith Cowan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1874422022-08-09T00:52:39Z2022-08-09T00:52:39ZBackyard hens’ eggs contain 40 times more lead on average than shop eggs, research finds<figure><img src="https://images.theconversation.com/files/478187/original/file-20220809-16-86bvbg.jpg?ixlib=rb-1.1.0&rect=0%2C33%2C4408%2C2908&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>There’s nothing like the fresh eggs from your own hens, the <a href="https://www.chickenguard.com.au/chicken-keeping-is-on-the-rise-australia/">more than 400,000</a> Australians who keep backyard chooks will tell you. Unfortunately, it’s often not just freshness and flavour that set their eggs apart from those in the shops. </p>
<p>Our <a href="https://doi.org/10.1016/j.envpol.2022.119798">newly published research</a>* found backyard hens’ eggs contain, on average, more than 40 times the lead levels of commercially produced eggs. Almost one in two hens in our Sydney study had significant lead levels in their blood. Similarly, about half the eggs analysed contained lead at levels that may pose a health concern for consumers.</p>
<p><a href="https://theconversation.com/the-verdicts-in-we-must-better-protect-kids-from-toxic-lead-exposure-41969">Even low levels</a> of lead exposure are considered <a href="https://www.atsdr.cdc.gov/toxprofiles/tp13.pdf">harmful to human health</a>, including among other effects <a href="https://www.thelancet.com/journals/lanpub/article/PIIS2468-2667(18)30025-2/fulltext">cardiovascular disease</a> and decreased IQ and kidney function. Indeed, the World Health Organization has <a href="https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health">stated</a> there is no safe level of lead exposure.</p>
<p>So how do you know whether this is a likely problem in the eggs you’re getting from backyard hens? It depends on lead levels in your soil, which vary across our cities. We mapped the areas of high and low risk for hens and their eggs in our biggest cities – Sydney, Melbourne and Brisbane – and present these maps here.</p>
<p><a href="https://doi.org/10.1016/j.envpol.2022.119798">Our research</a> details lead poisoning of backyard chickens and explains what this means for urban gardening and food production. In older homes close to city centres, contaminated soils can greatly increase people’s exposure to lead through eating eggs from backyard hens. </p>
<figure class="align-center ">
<img alt="chickens scratching in the dirt" src="https://images.theconversation.com/files/476428/original/file-20220728-20511-ejyizd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/476428/original/file-20220728-20511-ejyizd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/476428/original/file-20220728-20511-ejyizd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/476428/original/file-20220728-20511-ejyizd.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/476428/original/file-20220728-20511-ejyizd.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/476428/original/file-20220728-20511-ejyizd.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/476428/original/file-20220728-20511-ejyizd.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Chickens love scratching and pecking in the dirt. Unfortunately, that’s how lead from the soil gets into them.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>What did the study find?</h2>
<p>Most lead gets into the hens as they scratch in the dirt and peck food from the ground. </p>
<p>We assessed trace metal contamination in backyard chickens and their eggs from garden soils across 55 Sydney homes. We also explored other possible sources of contamination such as animal drinking water and chicken feed. </p>
<p>Our data confirmed what we had anticipated from our analysis of more than 25,000 garden samples from Australia gardens collected via the <a href="https://www.360dustanalysis.com/">VegeSafe program</a>. Lead is the <a href="https://www.mapmyenvironment.com/">contaminant of most concern</a>.</p>
<p>The amount of lead in the soil was significantly associated with lead concentrations in chicken blood and eggs. We found potential contamination from drinking water and commercial feed supplies in some samples but it is not a significant source of exposure. </p>
<hr>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/aehBQA0lH2M?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
</figure>
<hr>
<p>Unlike for <a href="https://www.nhmrc.gov.au/about-us/publications/managing-individual-exposure-lead-australia#block-views-block-file-attachments-content-block-1">humans</a>, there are no guidelines for blood lead levels for chickens or other birds. <a href="https://www.aavac.com.au/files/2015-16.pdf">Veterinary assessments</a> and research indicate levels of 20 micrograms per decilitre (µg/dL) or more may harm their health. Our analysis of 69 backyard chickens across the 55 participants’ homes showed 45% had blood lead levels above 20µg/dL. </p>
<p>We analysed eggs from the same birds. There are no food standards for trace metals in eggs in Australia or <a href="https://www.fao.org/fao-who-codexalimentarius/sh-proxy/en/?lnk=1&url=https%253A%252F%252Fworkspace.fao.org%252Fsites%252Fcodex%252FStandards%252FCXS%2B193-1995%252FCXS_193e.pdf">globally</a>. However, in the <a href="https://www.foodstandards.gov.au/publications/Pages/25th-Australian-Total-Diet-Study.aspx">19th Australian Total Diet Study</a>, lead levels were less than 5µg/kg in a small sample of shop-bought eggs. </p>
<p>The average level of lead in eggs from the backyard chickens in our study was 301µg/kg. By comparison, it was 7.2µg/kg in the nine commercial free-range eggs we analysed. </p>
<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4037389/">International research</a> indicates that eating one egg a day with a lead level of less than 100µg/kg would result in an estimated blood lead increase of less than 1μg/dL in children. That’s around the level <a href="https://www.mja.com.au/system/files/issues/212_04/mja250427.pdf">found in Australian children</a> not living in areas affected by lead mines or smelters. The <a href="https://www.nhmrc.gov.au/about-us/publications/managing-individual-exposure-lead-australia#block-views-block-file-attachments-content-block-1">level of concern used in Australia</a> for investigating exposure sources is 5µg/dL. </p>
<p>Some 51% of the eggs we analysed exceeded the 100µg/kg “food safety” threshold. To keep egg lead below 100μg/kg, our modelling of the relationship between lead in soil, chickens and eggs showed soil lead needs to be under 117mg/kg. This is much lower than the Australian residential guideline for soils of 300mg/kg. </p>
<p>To protect chicken health and keep their blood lead below 20µg/kg, soil concentrations need to be under 166mg/kg. Again, this is much lower than the guideline.</p>
<h2>How did we map the risks across cities?</h2>
<p>We used our garden soil trace metal database (more than 7,000 homes and 25,000 samples) to map the locations in Sydney, Brisbane and Melbourne most at risk from high lead values.</p>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of Sydney showing areas of high and low lead risk for backyard chickens" src="https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=569&fit=crop&dpr=1 600w, https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=569&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=569&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=715&fit=crop&dpr=1 754w, https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=715&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/476799/original/file-20220801-13622-gfamgw.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=715&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Levels of lead risk for backyard chickens across Sydney. Dark green dots indicate areas with safe lead levels. Light green and yellow dots are areas over the safe lead level. Orange and red dots indicate areas with high levels.</span>
<span class="attribution"><span class="source">Map: Max M. Gillings, Mark Patrick Taylor</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of Melbourne showing areas of high and low lead risk for backyard chickens" src="https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=569&fit=crop&dpr=1 600w, https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=569&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=569&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=715&fit=crop&dpr=1 754w, https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=715&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/476800/original/file-20220801-44691-cb37jb.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=715&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Map of Melbourne showing levels of lead risk for backyard chickens. Dark green dots indicate areas with safe lead levels. Light green and yellow dots are areas over the safe lead level. Orange and red dots indicate areas with high levels.</span>
<span class="attribution"><span class="source">Map: Max M. Gillings, Mark Patrick Taylor</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<hr>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Map of Brisbane showing areas of high and low lead risk for backyard chickens" src="https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=569&fit=crop&dpr=1 600w, https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=569&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=569&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=715&fit=crop&dpr=1 754w, https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=715&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/476801/original/file-20220801-13622-30yjyi.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=715&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Map of Brisbane showing levels of lead risk for backyard chickens. Dark green dots indicate areas with safe lead levels. Light green and yellow dots are areas over the safe lead level. Orange and red dots indicate areas with high levels.</span>
<span class="attribution"><span class="source">Map: Max M. Gillings, Mark Patrick Taylor</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<hr>
<p>Deeper analysis of the data showed older homes were much more likely to have high lead levels across soils, chickens and their eggs. This finding matches other studies that found older homes are most at risk of legacy contamination from the former use of lead-based paints, leaded petrol and lead pipes.</p>
<h2>What can backyard producers do about it?</h2>
<p>These findings will come as a shock to many people who have turned to backyard food production. It has been on the rise over the past decade, <a href="https://www.abc.net.au/news/2022-07-21/green-finger-boom-sprouts-from-rising-cost-of-living/101250928">spurred on recently</a> by soaring grocery prices.</p>
<p>People are <a href="https://australiainstitute.org.au/wp-content/uploads/2020/12/PB-59-Grow-Your-Own.pdf">turning to home-grown produce</a> for other reasons, too. They want to know where their food came from, enjoy the security of producing food with no added chemicals, and feel the closer connection to nature.</p>
<p>While urban gardening is a hugely important activity and should be encouraged, previous studies of <a href="https://www.sciencedirect.com/science/article/pii/S0160412021002075">contamination of Australian home garden soils</a> and <a href="https://www.sciencedirect.com/science/article/pii/S2352340921004352">trace metal uptake into plants</a> show it needs to be undertaken with caution. </p>
<p>Contaminants have built up in soils over the many years of our cities’ history. These legacy contaminants can enter our food chain via <a href="https://doi.org/10.1007/s11270-006-2027-1">vegetables</a>, <a href="https://doi.org/10.1021/acs.est.7b04084">honey bees</a> and <a href="https://doi.org/10.1016/j.scitotenv.2016.04.128">chickens</a>.</p>
<p>Urban gardening exposure risks have typically focused on <a href="https://doi.org/10.1016/j.envint.2018.10.054">vegetables and fruits</a>. Limited attention has been paid to backyard chickens. The challenge of sampling and finding participants meant many previous studies have been smaller and have not always analysed all possible exposure routes. </p>
<p>Mapping the risks of contamination in soils enables backyard gardeners and chicken keepers to consider what the findings may mean for them.</p>
<p>Particularly in older, inner-city locations, it would be prudent to get their soils tested. People can do this at <a href="https://www.360dustanalysis.com/">VegeSafe</a> or through a commercial laboratory. Soils identified as a problem can be replaced and chickens kept to areas of known clean soil.</p>
<hr>
<p><em>The authors acknowledge Tahereh Yazdanparast as first author of the research paper.</em></p><img src="https://counter.theconversation.com/content/187442/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Patrick Taylor received funding via an Australian Government Citizen Science Grant (2017-2020), CSG55984 ‘Citizen insights to the composition and risks of household dust’ (the DustSafe project). The VegeSafe and DustSafe programs are supported by publication donations to Macquarie University. He is a full-time employee of EPA Victoria, appointed to the statutory role of Chief Environmental Scientist.</span></em></p><p class="fine-print"><em><span>Dorrit E. Jacob and Vladimir Strezov do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Lead levels in backyard hen eggs are often much higher than in eggs bought in the shops. A new study of soil lead, chickens and eggs locates the high-risk areas in our biggest cities.Mark Patrick Taylor, Chief Environmental Scientist, EPA Victoria; Honorary Professor, Macquarie UniversityDorrit E. Jacob, Professor, Research School of Earth Sciences, Australian National UniversityVladimir Strezov, Professor, School of Natural Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1856852022-06-29T12:11:35Z2022-06-29T12:11:35ZClimate change is putting food safety at risk more often, and not just at picnics and parties – blackouts are a growing problem<figure><img src="https://images.theconversation.com/files/471485/original/file-20220628-14234-gop3kl.jpg?ixlib=rb-1.1.0&rect=491%2C0%2C4682%2C3086&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Dairy, meats and eggs can get risky when left in warm conditions.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/portrait-of-smiling-boy-holding-sandwich-with-his-royalty-free-image/691049473">Westend61 via Getty Images</a></span></figcaption></figure><p><em>Every year, <a href="https://www.cdc.gov/foodborneburden/2011-foodborne-estimates.html">almost 1 in 6 Americans</a> gets a foodborne illness, and about 3,000 people die from it, according to Centers for Disease Control and Prevention estimates. Picnics and parties where food sits out for hours are a common source, but heat waves and power outages are another silently growing threat.</em></p>
<p><em>As global temperatures rise, the risk of foods going bad during blackouts in homes or stores or during transit in hot weather rises with them. <a href="https://nutrition.tufts.edu/profile/faculty/elena-n-naumova">Elena Naumova</a>, an epidemiologist and data scientist at Tufts University, explains the risk and what you need to know to stay safe.</em></p>
<h2>What does climate change have to do with foodborne illness?</h2>
<p>The link between foodborne illness and climate change is quite straightforward: The pathogens that cause many foodborne infections are sensitive to temperature. That’s because warm, wet weather conditions stimulate bacterial growth.</p>
<p>Three main factors govern the spread of foodborne illness: 1) the abundance, growth, range and survival of pathogens in crops, livestock and the environment; 2) the transfer of these pathogens to food; and 3) human exposure to the pathogens.</p>
<p>Safety measures like warning labels and product recalls can help slow the spread of harmful bacteria and parasites, but these measures don’t always evolve rapidly enough to keep pace with the changing risk.</p>
<p>One growing problem is that heat waves, wildfires and severe storms are increasingly triggering power outages, which in turn affect food storage and food handling practices in stores, production and distribution sites and homes. A review of federal data in 2022 found that major U.S. <a href="https://apnews.com/article/wildfires-storms-science-business-health-7a0fb8c998c1d56759989dda62292379">power outages linked to severe weather had doubled</a> over the previous two decades. California often experiences <a href="https://www.bloomenergy.com/bloom-energy-outage-map/">smaller-scale outages</a> during heat waves and periods of high wildfire risk.</p>
<p>This can happen on the hottest and, in some areas, most humid days, creating ideal conditions for bacteria to grow.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/471456/original/file-20220628-14253-8980uj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/471456/original/file-20220628-14253-8980uj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=503&fit=crop&dpr=1 600w, https://images.theconversation.com/files/471456/original/file-20220628-14253-8980uj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=503&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/471456/original/file-20220628-14253-8980uj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=503&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/471456/original/file-20220628-14253-8980uj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=632&fit=crop&dpr=1 754w, https://images.theconversation.com/files/471456/original/file-20220628-14253-8980uj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=632&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/471456/original/file-20220628-14253-8980uj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=632&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Salmonella bacteria, in pink, a common cause of foodborne disease, invade a human epithelial cell.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/niaid/5613656967">NIAID</a></span>
</figcaption>
</figure>
<h2>Which causes of foodborne illness are increasing with the heat?</h2>
<p>Nationwide, many types of foodborne infection <a href="https://doi.org/10.1038/s41598-020-74435-9">peak in warm summer months</a>.</p>
<p><a href="https://www.cdc.gov/parasites/cyclosporiasis/gen_info/faqs.html"><em>Cyclospora</em></a>, a tiny parasite that causes intestinal infections and is transmitted through food or water contaminated with feces, often on imported vegetables and fruits, peaks in early June. </p>
<p>The bacteria <a href="https://www.cdc.gov/campylobacter/faq.html"><em>Campylobacter</em></a>, a common cause of diarrhea that’s often linked to undercooked meat; <a href="https://www.cdc.gov/vibrio/faq.html"><em>Vibrio</em></a>, linked to eating raw or undercooked shellfish; <a href="https://www.cdc.gov/salmonella/general/index.html"><em>Salmonella</em></a>, which causes diarrhea and is linked to animal feces; and STEC, a common type of <a href="https://www.cdc.gov/ecoli/general/index.html"><em>E. coli</em></a>, peak in mid-July. And the parasite <a href="https://www.cdc.gov/parasites/crypto/index.html"><em>Cyptosporidium</em></a>, germ <a href="https://www.cdc.gov/listeria/faq.html"><em>Listeria</em></a> and bacteria <a href="https://www.cdc.gov/shigella/general-information.html"><em>Shigella</em></a> peak in mid-August.</p>
<p>Many of these infections cause upset stomach, but they can also lead to severe diarrhea, dehydration, vomiting and even longer-term illnesses, such as meningitis and multiple organ failures.</p>
<figure class="align-center ">
<img alt="A man stands in front of a dark freezer case packed with pizzas and other frozen meals." src="https://images.theconversation.com/files/471487/original/file-20220628-14234-33ofq8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/471487/original/file-20220628-14234-33ofq8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=408&fit=crop&dpr=1 600w, https://images.theconversation.com/files/471487/original/file-20220628-14234-33ofq8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=408&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/471487/original/file-20220628-14234-33ofq8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=408&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/471487/original/file-20220628-14234-33ofq8.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=513&fit=crop&dpr=1 754w, https://images.theconversation.com/files/471487/original/file-20220628-14234-33ofq8.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=513&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/471487/original/file-20220628-14234-33ofq8.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=513&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">When refrigerators lose power, they can keep foods cool for only so long. This store owner in New York during the 2006 blackout said, ‘I’ll have to throw all this out.’</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/grocery-store-owener-asim-calik-surveys-a-freezer-full-of-news-photo/71510428">Chris Hondros/Getty Images</a>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In our studies, my colleagues and I have also found that <a href="https://doi.org/10.3390/ijerph19094947">food recalls increase</a> during summer months. </p>
<p>Typically, the U.S. sees about 70 foodborne outbreaks per month, with about two of them resulting in a food recall. In summer, the number of outbreaks can exceed 100 per month, and the number of recall-related outbreaks goes up to six per month, increasing from 3% to 6% of all reported and investigated outbreaks nationwide. </p>
<p>The rate of individual infections can also <a href="https://doi.org/10.1017/S0950268806006698">easily double or triple</a> the annual average during summer months. </p>
<p><iframe id="JhwJ1" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/JhwJ1/7/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<p>Precisely estimating infection numbers is very challenging because the vast majority of foodborne illness outbreaks – an estimated <a href="https://doi.org/10.1038/s41598-020-74435-9">80% of illnesses and 56% of hospitalizations</a> – are not attributed to known pathogens due to insufficient testing, and many foodborne illnesses are not even reported to the health authorities.</p>
<h2>What types of food should people worry about?</h2>
<p>Watch out for perishable products, including meat, poultry, fish, dairy and eggs, along with anything labeled as requiring refrigeration. How warm a food item can get before becoming risky varies, so the simplest rule for keeping food safe is to follow food labels and instructions.</p>
<p>The <a href="https://www.cdc.gov/foodsafety/index.html%5D(https://www.cdc.gov/foodsafety/index.html">CDC website</a> emphasizes four basic rules to prevent food poisoning at home: clean, separate, cook and chill.</p>
<p>It also offers some guidelines for when the power goes out, starting with keeping refrigerator and freezer doors closed. “A full freezer <a href="https://www.cdc.gov/foodsafety/food-safety-during-a-power-outage.html">will keep food safe for 48 hours</a> (24 hours if half-full) without power if you don’t open the door. Your refrigerator will keep food safe for up to four hours without power if you don’t open the door,” it says.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="An infographic offers advice also discussed in the article." src="https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=776&fit=crop&dpr=1 600w, https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=776&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=776&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=976&fit=crop&dpr=1 754w, https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=976&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/471484/original/file-20220628-14613-gop3kl.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=976&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Food safety tips.</span>
<span class="attribution"><a class="source" href="https://www.cdc.gov/foodsafety/food-safety-during-a-power-outage.html">CDC</a></span>
</figcaption>
</figure>
<p>After four hours without power or a cooling source, the CDC recommends that most meat, dairy, leftovers and cut fruits and vegetables in the refrigerator be thrown out.</p>
<p>Unfortunately, you cannot see, smell or taste many harmful pathogens that cause foodborne illness, so it’s better to be safe than sorry. Rule of thumb: When in doubt, throw it out.</p>
<h2>What’s the best response if a person gets sick from food?</h2>
<p>If you do get sick, it can be hard to pinpoint the culprit. Harmful bacteria can take anywhere from <a href="https://doh.wa.gov/you-and-your-family/food-safety/food-safety-myths">a few hours to several days</a> to make you sick. And people respond in different ways, so the same food might not make everyone ill.</p>
<p>Check with your doctor <a href="https://www.fda.gov/food/consumers/what-you-need-know-about-foodborne-illnesses">if you think you have food poisoning</a>. Get tested so your case will be reported. That helps public health authorities get a better sense of the extent of infections. The full extent of infections is typically vastly underreported.</p>
<p>I recommend checking health department websites, <a href="https://doh.wa.gov/you-and-your-family/food-safety/food-safety-myths">like Washington state’s</a>, for more advice, and <a href="https://www.fsis.usda.gov/recalls">check on food recalls</a> during the hot months.</p><img src="https://counter.theconversation.com/content/185685/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Elena N. Naumova receives funding from the National Science Foundation. She is affiliated with Tufts University. </span></em></p>Climate change has a clear link to rising foodborne illnesses. Blackouts during heat waves and wildfires are a growing part of the problem.Elena N. Naumova, Professor of Epidemiology and Data Science, Tufts UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1802992022-04-07T12:27:36Z2022-04-07T12:27:36ZBird flu is killing millions of chickens and turkeys across the US<figure><img src="https://images.theconversation.com/files/456423/original/file-20220405-22-wrzkbb.jpg?ixlib=rb-1.1.0&rect=3%2C0%2C2040%2C1354&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Avian flu spreads quickly through domestic poultry flocks.</span> <span class="attribution"><a class="source" href="https://flic.kr/p/asnRgD">Lance Cheung, USDA/Flickr</a></span></figcaption></figure><p><em>An <a href="https://www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/avian/avian-influenza/hpai-2022/2022-hpai-commercial-backyard-flocks">outbreak of Highly Pathogenic Avian Influenza</a> in chicken and turkey flocks has spread across 24 U.S. states since it was first detected in Indiana on Feb. 8, 2022. Better known as bird flu, avian influenza is a family of highly contagious viruses that are not harmful to wild birds that transmit it, but are deadly to domesticated birds. As of early April, the outbreak had caused the culling of some 23 million birds from Maine to Wyoming. <a href="https://scholar.google.com/citations?user=lLdLWigAAAAJ&hl=en">Yuko Sato</a>, an associate professor of veterinary medicine who works with poultry producers, explains why so many birds are getting sick and whether the outbreak threatens human health.</em></p>
<h2>Why is avian influenza so deadly for domesticated birds but not for wild birds that carry it?</h2>
<p>Avian influenza (AI) is a contagious virus that affects all birds. There are two groups of AI viruses that cause disease in chickens: highly pathogenic AI and low pathogenic AI. </p>
<p>HPAI viruses cause high mortality in poultry, and occasionally in some wild birds. LPAI can cause mild to moderate disease in poultry, and usually little to no clinical signs of illness in wild birds. </p>
<p>The primary <a href="https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section10.html">natural hosts and reservoir</a> of AI viruses are wild waterfowl, such as ducks and geese. This means that the virus is well adapted to them, and these birds do not typically get sick when they are infected with it. But when domesticated poultry, such as chickens and turkeys, come in direct or indirect contact with feces of infected wild birds, they become infected and start to show symptoms, such as <a href="https://www.cdc.gov/flu/avianflu/hpai/hpai-background-clinical-illness.htm">depression, coughing and sneezing and sudden death</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Wire cages hold chicken figurines" src="https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/456409/original/file-20220405-12-hkn2vr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Live birds are banned at agricultural fairs during bird flu outbreaks to avoid spreading infections. These fake chickens were on display at the Cabarrus County, N.C. fair in 2015, a previous H5N1 outbreak year.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/news-photo/real-birds-banned-at-state-fairs-due-to-bird-flu-these-are-news-photo/582537669">Elizabeth W. Kearley via Getty Images</a></span>
</figcaption>
</figure>
<h2>There are multiple strains of avian influenza. What type is this outbreak, and is it dangerous to humans?</h2>
<p>The virus of concern in this outbreak is a Eurasian H5N1 HPAI virus that causes high mortality and severe clinical signs in domesticated poultry. Scientists who <a href="https://www.usgs.gov/centers/nwhc/science/avian-influenza-surveillance">monitor wild bird flocks</a> have also detected a <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/genetic-reassortment">reassortant virus</a> that contains genes from both the Eurasian H5 and low pathogenic North American viruses. This happens when multiple strains of the virus circulating in the bird population exchange genes to create a new strain of the virus, much as new strains of COVID-19 like omicron and delta have emerged during the ongoing pandemic.</p>
<p>According to the U.S. Centers for Disease Control and Prevention, <a href="https://www.cdc.gov/flu/avianflu/spotlights/2021-2022/h5n1-low-risk-public.htm">the risk to public health from this outbreak is low</a>. No human illnesses have been associated with this virus in North America. That was also true of the <a href="https://www.cdc.gov/flu/avianflu/spotlights/2015/update-h5-outbreak-birds.htm">last H5N1 outbreak in the U.S. in 2014 and 2015</a>.</p>
<p><iframe id="KEnam" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/KEnam/2/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
<h2>Should people avoid poultry products until this outbreak ends?</h2>
<p>No, that’s not necessary. Infected poultry or eggs do not enter the food supply chain.</p>
<p>To detect AI, the U.S. Department of Agriculture oversees routine testing of flocks done by farmers and carries out federal inspection programs to ensure that eggs and birds are safe and free of virus. When H5N1 is diagnosed on a farm or in a backyard flock, state and federal officials will quarantine the site and cull and dispose of all the birds in the infected flock. Then the site is decontaminated. </p>
<p>After <a href="https://www.aphis.usda.gov/publications/animal_health/pos-hpai-stop-avian-influenza-outbreaks.508.pdf">several weeks</a> without new virus detections, the area is required to test negative in order to be deemed free of infection. We call this process the four D’s of outbreak control: diagnosis, depopulation, disposal and decontamination.</p>
<p>Avian influenza is not transmissible by eating properly prepared and cooked poultry, so eggs and poultry are safe to eat. The USDA recommends cooking eggs and poultry to an internal temperature of 165 degrees Fahrenheit (74 Celsius). </p>
<p></p>
<h2>Are avian influenza outbreaks happening more frequently around the world, or do we just hear more about them than we did 20 or 30 years ago?</h2>
<p>The dynamics of the spread of avian influenza viruses are very complex. HPAI is a transboundary disease, which means it is highly contagious and spreads rapidly across national borders. </p>
<p>Some research indicates that detection of HPAI viruses in wild birds <a href="https://doi.org/10.1002/jwmg.22171">has become more common</a>. Reports are seasonal, with a peak in February and a low point in September. There are ongoing outbreaks of HPAI in wild birds in Asia, Europe and Africa. Many migratory bird species <a href="https://www.usgs.gov/centers/nwhc/science/avian-influenza">travel thousands of miles between continents</a>, posing a continuing risk of AI virus transmission.</p>
<p>In addition, we have better diagnostic tests for much more rapid and improved detection of avian influenza compared to 20 to 30 years ago, using molecular diagnostics such as <a href="https://www.webmd.com/lung/coronavirus-glossary#1">polymerase chain reaction (PCR) tests</a> – the same method labs use to detect COVID-19 infections. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/YmK4V66trbQ?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Farmers can take steps to make their flock more biosecure, such as preventing birds and their feed from being exposed to wild birds.</span></figcaption>
</figure>
<h2>What’s the prospect of developing a vaccine for poultry that could reduce the economic harm from outbreaks?</h2>
<p>Many factors would have to be weighed before adopting vaccination as a strategy for controlling HPAI. At this time, the Department of Agriculture has not approved the use of vaccination in the U.S. for protecting birds from avian influenza.</p>
<p>One reason for this is that using vaccines would potentially affect international trade and poultry exports. Importers would not be able to distinguish vaccinated birds from infected birds based on the routine testing, so they might ban all U.S. poultry exports. </p>
<p>Vaccination also <a href="https://www.reuters.com/world/us/us-considers-vaccines-protect-poultry-deadly-bird-flu-2022-04-04/">could delay outbreak detection</a>, since it can potentially hide non-apparent infections in infected birds. And if infections go unnoticed, they could spread to other farms before farmers can put control measures in place. </p>
<p>Avian influenza vaccines can reduce clinical signs, sickness and death rates in domestic poultry, but they would not prevent birds from becoming infected with the virus. Ultimately, the USDA’s goal is to <a href="https://www.aphis.usda.gov/aphis/ourfocus/animalhealth/animal-disease-information/avian/avian-influenza/defend-the-flock-hpai">eradicate HPAI quickly after it is detected</a>. However, vaccines could be used to help control an outbreak, and this is an option that the agency <a href="https://www.usda.gov/media/blog/2022/02/28/creating-better-vaccines">is investigating now</a>.</p>
<p>[<em>You’re smart and curious about the world. So are The Conversation’s authors and editors.</em> <a href="https://memberservices.theconversation.com/newsletters/?source=inline-youresmart">You can read us daily by subscribing to our newsletter</a>.]</p><img src="https://counter.theconversation.com/content/180299/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Yuko Sato receives funding from the US Department of Agriculture, the Bill and Melinda Gates Foundation, allied industry companies, the Pew Foundation, the Egg Industry Center, the US Poultry & Egg Association, and internally through Iowa State University. She is affiliated with the Iowa Poultry Association, the Iowa Turkey Federation, United Egg Producers and the US Animal Health Association. </span></em></p>Bird flu is highly contagious in domestic flocks, and a major outbreak is underway in the US. A veterinary scientist explains what consumers need to know.Yuko Sato, Associate Professor of Veterinary Medicine, Iowa State UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1771182022-03-28T12:37:55Z2022-03-28T12:37:55ZHow did cockroaches survive the asteroid that led to the extinction of dinosaurs?<figure><img src="https://images.theconversation.com/files/453979/original/file-20220323-19-1ijv5iq.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C5000%2C3495&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artist's rendering of the Chicxulub asteroid entering Earth's atmosphere 66 million years ago, triggering events that caused a mass extermination.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/illustration/end-of-cretaceous-kt-event-illustration-royalty-free-illustration/724237133">Roger Harris/Science Photo library via Getty Images</a></span></figcaption></figure><figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=293&fit=crop&dpr=1 600w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=293&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=293&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=368&fit=crop&dpr=1 754w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=368&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/281719/original/file-20190628-76743-26slbc.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=368&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption"></span>
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<p><em><a href="https://theconversation.com/us/topics/curious-kids-us-74795">Curious Kids</a> is a series for children of all ages. If you have a question you’d like an expert to answer, send it to <a href="mailto:curiouskidsus@theconversation.com">curiouskidsus@theconversation.com</a>.</em></p>
<hr>
<blockquote>
<p><strong>How did cockroaches survive the asteroid that led to the extinction of dinosaurs? – Kinjal, age 11, Delhi, India</strong></p>
</blockquote>
<p>When the rock now known as the <a href="https://www.nytimes.com/2021/09/13/science/chicxulub-dinosaur-extinction.html">Chicxulub impactor</a> plummeted from outer space and slammed into the Earth 66 million years ago, cockroaches were there. The impact caused a massive earthquake, and scientists think it also <a href="https://theconversation.com/more-bad-news-for-dinosaurs-chicxulub-meteorite-impact-triggered-global-volcanic-eruptions-on-the-ocean-floor-91053">triggered volcanic eruptions</a> thousands of miles from the impact site. Three-quarters of plants and animals on Earth died, including all dinosaurs, <a href="https://www.birdlife.org/news/2021/12/21/its-official-birds-are-literally-dinosaurs-heres-how-we-know/">except for some species</a> that were ancestors of today’s birds.</p>
<p>How could roaches a couple of inches long survive when so many powerful animals went extinct? It turns out that they were nicely equipped to live through a meteoric catastrophe.</p>
<p>If you’ve ever seen a cockroach, you’ve probably noticed that their bodies are very flat. This is not an accident. Flatter insects can squeeze themselves into tighter places. This enables them to hide practically anywhere – and it may have helped them survive the Chicxulub impact.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/1ro6PNqkHEM?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Cockroaches have flat bodies that help them squeeze through tiny spaces. They’re also strong and fast.</span></figcaption>
</figure>
<p>When the meteor struck, <a href="https://www.smithsonianmag.com/science-nature/dinosaur-killing-asteroid-impact-chicxulub-crater-timeline-destruction-180973075/">temperatures on Earth’s surface skyrocketed</a>. Many animals had nowhere to flee, but roaches could take shelter in tiny soil crevices, which provide excellent protection from heat.</p>
<p>The meteor’s impact <a href="https://www.livescience.com/dinosaur-killing-asteroid-struck-earth">triggered a cascade of effects</a>. It kicked up so much dust that the sky darkened. As the sun dimmed, temperatures plunged and conditions became wintry around the globe. With little sunlight, surviving plants struggled to grow, and many other organisms that relied on those plants went hungry. </p>
<p>Not cockroaches, though. Unlike some insects that <a href="https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/yucca_moths.shtml">prefer to eat one specific plant</a>, cockroaches are <a href="https://cockroachfacts.com/what-do-cockroaches-eat/">omnivorous scavengers</a>. This means they will eat most foods that come from animals or plants as well as cardboard, some kinds of clothing and even poop. Having appetites that aren’t picky has allowed cockroaches to survive lean times since the Chicxulub extinction and other natural disasters.</p>
<p>Another helpful trait is that cockroaches <a href="https://extension.umn.edu/insects-infest-homes/cockroaches">lay their eggs in little protective cases</a>. These egg cartons look like dried beans and are called oothecae, which means “egg cases.” Like phone cases, oothecae are hard and protect their contents from physical damage and other threats, such as flooding and drought. Some cockroaches may have waited out part of the Chicxulub catastrophe from the comfort of their oothecae. </p>
<figure class="align-right ">
<img alt="Small brown rectangular egg case on white background" src="https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/453995/original/file-20220323-17-10395k5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cockroach egg cases are about 0.5 inches long (10 millimeters) and contain up to 50 eggs, depending on the species.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/ootheca-of-cockroach-isolated-on-white-royalty-free-image/488873689">VitalisG/iStock via Getty Images</a></span>
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<p>Modern cockroaches are little survivors that can live just about anywhere on land, from the heat of the tropics to some of the coldest parts of the globe. Scientists estimate that <a href="https://bugguide.net/node/view/342386">there over 4,000 cockroach species</a>. </p>
<p>A handful of these species like to live with humans and quickly become pests. Once cockroaches become established in a building, it’s hard to rid every little crack of these insects and their oothecae. When large numbers of roaches are present in unsanitary places, they can spread diseases. The biggest threat they pose to human health is from allergens they produce that can <a href="https://www.nytimes.com/2018/08/03/science/cockroach-diseases.html">trigger asthma attacks and allergic reactions</a> in some people.</p>
<p>Cockroach pests are hard to manage because they can <a href="https://www.nationalgeographic.com/animals/article/pesticides-are-making-german-cockroaches-stronger">resist many chemical insecticides</a> and because they have the same abilities that helped their ancestors outlive many dinosaurs. Still, cockroaches are much more than a pest to control. Researchers study cockroaches to understand <a href="https://news.umich.edu/lessons-from-cockroaches-could-inform-robotics/">how they move</a> and <a href="https://www.nytimes.com/2016/02/09/science/cockroaches-indestructible-and-instructive-to-robot-makers.html">how their bodies are designed</a> to get ideas for building better robots.</p>
<p><a href="https://www.researchgate.net/profile/Brian-Lovett">As a scientist</a>, I see all insects as beautiful, six-legged inspirations. Cockroaches have already overcome odds that were too great for dinosaurs. If another meteorite hit the Earth, I’d be more worried for humans than for cockroaches.</p>
<hr>
<p><em>Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to <a href="mailto:curiouskidsus@theconversation.com">CuriousKidsUS@theconversation.com</a>. Please tell us your name, age and the city where you live.</em></p>
<p><em>And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.</em></p><img src="https://counter.theconversation.com/content/177118/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Brian Lovett does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Cockroaches have been on Earth far longer than humans and may outlast us. Here are a few reasons why.Brian Lovett, Postdoctoral Researcher in Mycology, West Virginia UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1726162022-02-18T03:17:49Z2022-02-18T03:17:49ZSunny side up: can you really fry an egg on the footpath on a hot day?<figure><img src="https://images.theconversation.com/files/436864/original/file-20211210-159504-1hfdr6i.jpg?ixlib=rb-1.1.0&rect=10%2C0%2C2385%2C1598&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Aahh, the Australian summer. When the temperatures top 40°C and only the bravest or most foolhardy would venture outside in bare feet, there’s a cherished old saying: “it’s so hot outside you could fry an egg on the footpath!” </p>
<p>But what does the science say? Does this claim stack up, or it half-baked?</p>
<p>To answer this question, we need to understand the chemicals inside an egg, what happens to them during the cooking process, and whether the footpath really gets hot enough to drive these chemical changes.</p>
<p>The first and most obvious point is that the egg’s yolk and white are <a href="https://www.compoundchem.com/2016/03/26/eggs/">chemically very different</a>. The white, which makes up about two-thirds of an egg’s mass, is roughly nine parts water and one part protein. The key here is that the protein’s structure changes if you heat it above a certain temperature.</p>
<p>About half the yolk’s mass is water, about a quarter is “fat”, about one-sixth is protein, and less than 5% is carbohydrates. The protein in the yolk is a completely different type of protein, but much like with the egg white, it’s how the protein responds to heat that gives us the texture of fried, scrambled, poached or hard-boiled eggs.</p>
<h2>Ok, so how does this work?</h2>
<p>We can think of proteins as being long chains of molecules called amino acids. In a raw egg, the protein is suspended in the watery mixture. The chain is curled up in a very particular way, held in shape by weak chemical bonds between different parts of the chain as it folds over on itself (the animation below shows the folded structure of ovalbumin, the main protein in egg white). This keeps it stable, and able to mix with the water. </p>
<p><img src="https://cdn.theconversation.com/static_files/files/1895/protein_animation.gif?1639369721" width="100%"></p>
<p>But once it’s heated up, the heat energy starts to break these weak chemical bonds and the chain begins to uncurl, rearrange itself and stick together again in a completely different way.</p>
<p>Suddenly, these reconfigured clumps of protein molecules are no longer water-soluble, and so they solidify. This is why eggs get harder if you cook them for longer.</p>
<p>This process is called <em>denaturation</em>, and it can happen to any type of protein. Denaturation is what turns milk into curds and whey, and changes the texture of meat as it cooks.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/kitchen-science-the-chemistry-behind-amazing-meringue-and-perfect-cappuccino-64670">Kitchen Science: the chemistry behind amazing meringue and perfect cappuccino</a>
</strong>
</em>
</p>
<hr>
<p>For eggs, denaturation begins at around 60°C, but this is likely to only slightly cook the egg whites, and the yolk will <a href="https://blogs.unimelb.edu.au/sciencecommunication/2014/08/18/the-perfect-egg/">not turn solid at all</a>.</p>
<p>As you slowly go from 60°C to 70°C, however, there is more heat energy available and all of the egg’s proteins now begin to denature. The egg white begins to turn gel-like and eventually rubbery, and the yolk begins to solidify into a viscous goo, before eventually becoming solid or even slightly powdery in texture.</p>
<p>Get the temperature right and this process unfolds nice and gradually, which means with a bit of practice you can get your eggs to turn out exactly how you like them.</p>
<h2>Righto, so is a footpath hot enough for this?</h2>
<p>That leaves us with the crucial question: how hot does pavement get on a scorching summer day? Does it reach the almost 70°C you would need for a footpath fry-up?</p>
<p>This depends on a lot of factors, including the air temperature, direct sunlight, the footpath material and even its colour. Black-painted concrete, for example, absorbs more heat than white or unpainted concrete. </p>
<p>All in all, at the peak of these conditions, on a boiling summer day, a footpath can potentially just about reach the right temperature. But sadly, that’s still not enough to sizzle an egg.</p>
<p>First, concrete is a poor conductor, so it will transfer heat to the egg much more slowly than a metal frying pan. Second, after cracking the egg onto the footpath, the footpath’s temperature will drop slightly.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-you-cant-fry-eggs-or-testicles-with-a-cellphone-70636">Why you can’t fry eggs (or testicles) with a cellphone</a>
</strong>
</em>
</p>
<hr>
<p>So if you were hoping for a cheap way to cook your sunny-side-up eggs on the footpath this summer, you might be disappointed. It’s much wiser to head back indoors to the kitchen. Your egg will be hotter, and you’ll be much cooler.</p><img src="https://counter.theconversation.com/content/172616/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Chris Thompson does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It’s too hot for bare feet, but that doesn’t mean you can cook a fry-up on the path outside your house. A frying pan is a much better tool for the job, because it conducts heat far more efficiently.Chris Thompson, Associate Dean (Education) - Science, Monash UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1690952021-10-27T19:11:56Z2021-10-27T19:11:56ZWhy are birds’ eggs colourful? New research shows it’s linked to the shape of their nests<figure><img src="https://images.theconversation.com/files/425142/original/file-20211006-15-b30uh7.jpg?ixlib=rb-1.1.0&rect=6%2C61%2C2150%2C2635&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption"></span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p>Of all the vertebrates on Earth – that is, animals with backbones – birds are the only ones that lay colourful eggs. Scientists are still unsure why, but new research brings us a step closer to finding out. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427409/original/file-20211020-23-1ud4f77.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Although most reptiles lay eggs, and even some mammals (such as the platypus) too, birds are the only backboned animals alive today that can lay colourful and patterned eggs.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>In a <a href="https://doi.org/10.1111/evo.14375">study</a> published today in the journal Evolution, my colleagues and I reveal how the colours of songbird eggs diversified alongside the evolution of “open cup” nests, more than 40 million years ago. </p>
<h2>Why are eggs colourful?</h2>
<p>Scientists are not entirely sure why birds lay such colourful eggs. Current <a href="https://onlinelibrary.wiley.com/doi/pdf/10.1017/S1464793106007044?casa_token=rVWsE2UoW1cAAAAA:XRVTVbEe1lY_TlM9FPw3zMdHwDDZkiGp2SjlGIVej6XE6T4gA0sUVvKSABr3ZhiwMUM6hE3H8-Vdz34">theories</a> fall into two main categories.</p>
<p>The first is that colour helps protect the eggs from environmental factors such as extreme cold or rain. Eggs with darker pigments <a href="https://www.nature.com/articles/s41559-019-1003-2">heat up faster</a> and maintain heat longer than white eggs. Pigments have also been shown to help <a href="https://journals.sagepub.com/doi/pdf/10.3184/175815511X13207833399666?casa_token=HiN3QnhKbo4AAAAA:3Asv0MtnKLcedUJmSJ8Ejsg3qIyFBrB__5OUwCA2qA582JL1oK6u5fWj-dzEU32bWAa6E5_J4fdd">strengthen thinner eggshells</a>. </p>
<p>Eggshells can show areas of thinning, usually when the female’s diet is lacking calcium. This can often result from the use of pesticides, including DDT, in the wild – as they can dissolve or contaminate otherwise nutritious food such as snail shells.</p>
<p>Females have been shown to deposit pigments in the same spots where a shell is thinner (and more prone to breaking) – a bit like covering it with plaster. This may reinforce the shell and help keep it structurally sound. </p>
<p>We know the pigments are produced in the female’s uterus during the shell’s formation, but it’s still not known how different colours and complex patterns are applied to the shell while the egg is still inside the female. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hot-as-shell-birds-in-cooler-climates-lay-darker-eggs-to-keep-their-embryos-warm-125921">Hot as shell: birds in cooler climates lay darker eggs to keep their embryos warm</a>
</strong>
</em>
</p>
<hr>
<p>The second theory is that colour provides a survival advantage, either by camouflaging the eggs from predators or parasites, or by signalling the female’s reproductive fitness to potential partners. More colourful eggs, particularly blue, <a href="https://doi.org/10.1525/cond.2008.8634">signify</a> the mother is healthy and can spare resources for her babies.</p>
<h2>How is the colour made?</h2>
<p>All the colours we see in bird eggs stem from just two pigments, one brown and the other blue. Different concentrations of these two pigments create the vast range of egg colours we see today.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427410/original/file-20211020-15-1qi1fmk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Some eggs have intricate and delicate patterns. We still don’t know how the female birds apply the pigments to the eggshell in this way.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>Until 2017, scientists believed laying colourful eggs was a trait unique to birds. But as it turns out, the same pigments can be found in fossilised <a href="https://peerj.com/articles/3706/">dinosaur eggs</a> too.</p>
<p>Researchers also found a link between dinosaurs’ nesting behaviour and egg colour. Specifically, they discovered dinosaurs that laid their eggs in partially open nests (rather than burying them like crocodiles) had colour in their eggshells. </p>
<h2>Nest-building through time</h2>
<p>Until about 40 million years ago, songbirds built complex dome-shaped nests with insulated walls and roofs. Over time, however, they evolved the ability to create the open cup nests we see more commonly today. </p>
<p>Birds exhibit fantastic dexterity when building nests. Using only their beaks and feet, they can weave an array of nests ranging from relatively rudimentary designs to substantial, intricately woven structures. </p>
<p>The nests must have enough structural integrity to hold both the eggs and the weight of an incubating parent without being punctured. They must also stay intact while parents move around, hatched chicks start wriggling, and during rainfall and harsh winds. </p>
<p>Now, our research has found a link between eggshell colour and changes in nest construction. Specifically, birds have gone from laying a narrower range of coloured eggs (mainly white or dark brown) in closed dome nests, to a wider variety of colours (white, pink, olive, blue, pink and brown) in cup nests.</p>
<p>The transition to cup nests means the eggs are exposed when the incubating parent leaves to forage. During these foraging bouts, eggs are much more vulnerable to falling outside the temperature range needed to survive. </p>
<p>If they get too cold or hot, the embryos die. They’re also more exposed to passing predators looking for a snack. </p>
<p>Parasitic cuckoos lay their eggs inside other birds’ nests, and match their eggs to those already in the nest. Perhaps colour started playing an essential role in host parents’ evolutionary attempts to thwart the cuckoos?</p>
<p>Back when nests were mostly closed, and eggs hidden, the host wouldn’t have needed to produce colourful eggs to distinguish them from the cuckoo’s. Similarly, cuckoos wouldn’t have needed to match their eggs with the host’s.</p>
<p>Our research found that laying colourful eggs is a flexible trait, and was lost and regained multiple times during songbirds’ evolutionary history. Moreover, birds that evolved to make cup nests lost and regained this trait twice as many times as birds that still make closed nests today.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/who-would-win-in-a-fight-between-an-emu-and-a-cassowary-one-has-a-dagger-like-claw-the-other-explosive-agility-160540">Who would win in a fight between an emu and a cassowary? One has a dagger-like claw, the other explosive agility</a>
</strong>
</em>
</p>
<hr>
<h2>Onward, upward</h2>
<p>In the 1800s naturalists had a fascination with birds’ eggs, and it became common to own extensive egg collections. The ultimate goal for collectors, other than prestige, was to have as many different species as possible. </p>
<p>Today, collecting specimens is quite understandably illegal. But those old collections do come in handy. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A collection of bird eggs, in various colours and patterns, in a museum tray." src="https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/427408/original/file-20211020-19-1i8tpcb.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Today, it’s illegal to collect or trade native bird eggs in Australia without a permit.</span>
<span class="attribution"><span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>For our work, we were able to draw on extensive egg collections donated to museums in Australia. We measured the egg colours of more than 250 different species of Australian songbird, took photographs, and analysed them against their evolutionary histories. </p>
<p>Many of the eggs from museum collections also come with geographical locations. We’re grateful to early naturalists for making extensive notes on where, when and how they collected each clutch.</p>
<p>Moving forward, we want to use this data to investigate how climatic variables interact with egg colour — as well as whether a female’s diet impacts egg colour. Egg-citing stuff! </p>
<hr>
<p><em>We would like to acknowledge the Traditional Owners of the land from which these eggs were taken, and pay our respects to the Elders, past and present and emerging.</em></p><img src="https://counter.theconversation.com/content/169095/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kiara L'Herpiniere does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>It’s still not known exactly how female birds produce such colourful and intricately-patterned eggs. But we do have some theories about the survival advantage this provides.Kiara L'Herpiniere, PhD Candidate, Wildlife Biologist, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1635522021-07-05T06:48:37Z2021-07-05T06:48:37ZNational plan to allow battery cages until 2036 favours cheap eggs over animal welfare<figure><img src="https://images.theconversation.com/files/409622/original/file-20210705-19-1oft08e.jpg?ixlib=rb-1.1.0&rect=23%2C34%2C7741%2C5098&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Eggs laid by battery hens would be phased out within 15 years under a plan to improve poultry welfare in Australia. The proposal signals some relief for the <a href="https://www.australianeggs.org.au/dms/4858-AE-Anuual-Report-2020-V8-web.pdf">10 million</a> or so egg-laying hens still kept in battery cages in Australia. But it doesn’t go far enough.</p>
<p>Among <a href="https://parlinfo.aph.gov.au/parlInfo/download/publications/tabledpapers/f24e63d8-5fab-4736-b62a-0ca637a63a08/upload_pdf/OPD%201146_Redacted.pdf">the recommendations</a> of an independent panel were to phase out battery cages between 2032 and 2036. Egg producers will have the option of transitioning to larger furnished cages, or may decide to move straight to cage-free systems, such as barn-laid and free-range eggs.</p>
<p>Such recommendations may seem like a happy compromise – balancing the interests of farmers, consumers and the hens themselves. </p>
<p>But developing welfare standards for farmed animals involves more than just practical, scientific and economic considerations. Such decisions also have an ethical dimension: what level of animal welfare <em>should</em> society provide? On that measure, we believe the standards fall short.</p>
<figure class="align-center ">
<img alt="two cartons of eggs - one free-range, one caged" src="https://images.theconversation.com/files/409612/original/file-20210705-27-n97uyp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409612/original/file-20210705-27-n97uyp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409612/original/file-20210705-27-n97uyp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409612/original/file-20210705-27-n97uyp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409612/original/file-20210705-27-n97uyp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=502&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409612/original/file-20210705-27-n97uyp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=502&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409612/original/file-20210705-27-n97uyp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=502&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Under the draft standards, from 2036 no battery hens would be allowed in Australia.</span>
<span class="attribution"><span class="source">Alan Porritt/AAP</span></span>
</figcaption>
</figure>
<h2>An appetite for change</h2>
<p>An independent panel drafted <a href="https://parlinfo.aph.gov.au/parlInfo/download/publications/tabledpapers/f24e63d8-5fab-4736-b62a-0ca637a63a08/upload_pdf/OPD%201146_Redacted.pdf">the proposal</a> after consulting state and territory governments, industry, animal welfare groups and the public. </p>
<p>The draft standards cover poultry including chickens, ducks, emus, geese, quail and turkeys. Confining hens in battery cages is by far the industry’s most controversial practice, and we focus on those recommendations here.</p>
<p><a href="https://link.springer.com/article/10.1007/s10071-016-1064-4">Research has found</a> hens are intelligent, social animals. But confined to battery cages – often a space <a href="https://www.poultryworld.net/Eggs/Articles/2021/6/European-Parliament-votes-to-ban-the-use-of-cages-by-2027-758070E/">smaller</a> than an A4 sheet of paper – they <a href="https://agriculture.vic.gov.au/__data/assets/pdf_file/0008/529829/Farmed-Bird-Welfare-Science-Review.pdf">cannot</a> stretch their wings or perform basic natural behaviours such as roost, nest, forage and dust-bathe. </p>
<p>Battery hens can also suffer <a href="https://agriculture.vic.gov.au/__data/assets/pdf_file/0008/529829/Farmed-Bird-Welfare-Science-Review.pdf">severe health problems</a> such as feather loss, fractured bones and haemorrhagic fatty liver syndrome. They can also experience <a href="https://welfarefootprint.org/research-projects/laying-hens/">more pain</a> than those in cage-free systems.</p>
<p>Industry figures <a href="https://www.australianeggs.org.au/dms/4858-AE-Anuual-Report-2020-V8-web.pdf">show</a> Australia produces around 17 million eggs each day. Of about 75% sold at supermarkets, 39% are from caged hens. Free-range (50%), barn-laid (10%) and specialty eggs (1%) make up the remainder. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/not-just-activists-9-out-of-10-people-are-concerned-about-animal-welfare-in-australian-farming-117077">Not just activists, 9 out of 10 people are concerned about animal welfare in Australian farming</a>
</strong>
</em>
</p>
<hr>
<p>Of the other 25%, much is used in processed foods and catering, where the proportion of cage eggs is <a href="https://www.abc.net.au/news/2021-06-23/caged-eggs-phased-out-by-2036-under-national-proposal/100236246">thought to be higher</a> than those sold in supermarkets.</p>
<p>Cage-free eggs are generally more expensive than cage eggs. Nonetheless, <a href="https://theconversation.com/its-no-yolk-grocery-giants-commit-to-animal-welfare-initiatives-12083">major supermarkets</a> and other food companies have also vowed to phase out caged eggs, or <a href="https://www.rspca.org.au/take-action/layer-hen-welfare/cage-free-proud">already use cage-free eggs</a> in their products.</p>
<p>A <a href="https://www.outbreak.gov.au/sites/default/files/documents/farm-animal-welfare.pdf">2018 report</a> prepared for the federal government found 95% of Australians view the welfare of farmed animals as a concern and 91% want law reform to address it. </p>
<p>It found Australians want regulation that prevents the suffering of farmed animals, which are increasingly seen as sentient beings with capabilities, rights and freedoms.</p>
<p>Keeping hens in cages is not consistent with these views. An <a href="https://www.animalhealthaustralia.com.au/news/record-response-poultry-welfare-standards-public-consultation">unprecedented</a> 170,000-odd <a href="http://www.animalwelfarestandards.net.au/files/2015/07/Public-consultation-report-final-09072018.pdf">public submissions</a> were made on the draft poultry standards, reflecting the huge public interest in the issue. The vast majority supported a ban on battery cages. </p>
<figure class="align-center ">
<img alt="free range hens feeding" src="https://images.theconversation.com/files/409616/original/file-20210705-27-olfa3w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409616/original/file-20210705-27-olfa3w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409616/original/file-20210705-27-olfa3w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409616/original/file-20210705-27-olfa3w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409616/original/file-20210705-27-olfa3w.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409616/original/file-20210705-27-olfa3w.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409616/original/file-20210705-27-olfa3w.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Under the proposal, hens would be free-range or kept in barns or larger cages.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<h2>How did we get here?</h2>
<p>State and territory agriculture ministers must now endorse the standards and enact regulations to bring them into effect.</p>
<p>If enacted, the standards will replace the <a href="https://www.publish.csiro.au/ebook/download/pdf/3451">outdated</a> 2002 code of practice. The independent panel was appointed to help re-draft those standards after previous attempts were mired in controversy, including <a href="https://www.abc.net.au/news/2017-12-21/egg-farmers-accused-of-colluding-with-nsw-government/9229242">allegations</a> of collusion between farmers and the NSW government.</p>
<p><a href="https://www.smh.com.au/business/consumer-affairs/rspca-threatens-to-quit-poultry-standards-advisory-group-as-integrity-of-process-is-questioned-20170213-gubgx0.html">Scientists</a>, <a href="https://www.smh.com.au/business/consumer-affairs/rspca-threatens-to-quit-poultry-standards-advisory-group-as-integrity-of-process-is-questioned-20170213-gubgx0.html">animal welfare organisations</a> and <a href="https://www.abc.net.au/news/2017-12-22/western-australia-may-leave-chicken-welfare-review/9283274">two state governments</a> also raised concern about the integrity of the process.</p>
<p>The panel’s appointment was a positive step. Importantly, it was made up of independent experts, rather than dominated by industry and agriculture department representatives.</p>
<figure class="align-center ">
<img alt="hens in cage with feathers missing" src="https://images.theconversation.com/files/409614/original/file-20210705-19-10b71u7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409614/original/file-20210705-19-10b71u7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409614/original/file-20210705-19-10b71u7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409614/original/file-20210705-19-10b71u7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409614/original/file-20210705-19-10b71u7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409614/original/file-20210705-19-10b71u7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409614/original/file-20210705-19-10b71u7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Most submissions supported a ban on keeping hens in battery cages, which can cause serious health problems.</span>
<span class="attribution"><span class="source">Emma Hanswell/AAP</span></span>
</figcaption>
</figure>
<h2>Where the proposal falls short</h2>
<p>The proposed standards give egg producers ten to 15 years to transition away from battery cages. Animal welfare groups such as the <a href="https://www.abc.net.au/news/2021-06-23/caged-eggs-phased-out-by-2036-under-national-proposal/100236246">RSPCA say</a> this timeline is too slow and cages should be phased out sooner – and we agree.</p>
<p>The use of battery cages in Australia is certainly <a href="https://theconversation.com/proposed-poultry-standards-leave-australia-trailing-behind-other-industrialised-countries-88302">out of step</a> internationally. Most OECD nations have <a href="https://www.parliament.nsw.gov.au/lcdocs/transcripts/2188/Transcript%20-%2014%20August%20-%20Select%20Committee%20on%20the%20Use%20of%20Battery%20Cages%20for%20Hens%20in%20the%20Egg%20-%20UNCORRECTED.pdf">banned</a> battery cages or are in the process of doing so.</p>
<p>The lengthy period of transition prioritises the continued availability of cheap battery cage eggs, and the interests of cage-egg producers, over the welfare of millions of animals.</p>
<p>The standards will still allow the use of <a href="https://pubmed.ncbi.nlm.nih.gov/12365505/">furnished cages</a>: larger cages with features such as perches and scratch pads.</p>
<p>Furnished cages are better than battery cages. And some researchers <a href="https://agriculture.vic.gov.au/__data/assets/pdf_file/0008/529829/Farmed-Bird-Welfare-Science-Review.pdf">say</a> furnished cages, if well managed, are better than poorly run free-range and barn systems. But the behavioural needs of hens are not fully satisfied in furnished cages. And if lifetime confinement represents a “better” animal welfare outcome than many cage-free facilities, this reflects very poorly on the regulation of cage-free systems. </p>
<p>A more humane approach would keep hens in well-managed free-range or barn systems. In fact, the European Parliament last month <a href="https://www.poultryworld.net/Eggs/Articles/2021/6/European-Parliament-votes-to-ban-the-use-of-cages-by-2027-758070E/">voted overwhelmingly</a> (but non-bindingly) in favour of phasing out all cages in farming.</p>
<p>And enacting new standards is not enough. To ensure standards are maintained and enforced, an independent animal welfare regulator is needed, as recommended by the <a href="https://www.pc.gov.au/inquiries/completed/agriculture/report">Productivity Commission</a> in 2017. </p>
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<img alt="three hens in field" src="https://images.theconversation.com/files/409625/original/file-20210705-35953-1pt8cxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/409625/original/file-20210705-35953-1pt8cxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=262&fit=crop&dpr=1 600w, https://images.theconversation.com/files/409625/original/file-20210705-35953-1pt8cxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=262&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/409625/original/file-20210705-35953-1pt8cxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=262&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/409625/original/file-20210705-35953-1pt8cxy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=330&fit=crop&dpr=1 754w, https://images.theconversation.com/files/409625/original/file-20210705-35953-1pt8cxy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=330&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/409625/original/file-20210705-35953-1pt8cxy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=330&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">An independent regulator should enforce poultry standards.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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<h2>A fundamental moral question</h2>
<p>The draft standards represent an important first step in freeing Australian hens from cages. While not perfect, they will bring Australian agriculture closer to international scientific consensus and public opinion on the issue.</p>
<p>However, developing animal welfare standards involves considering the practical, the economic, the scientific <em>and</em> the ethical. Deciding whether and when to ban cage production systems touches on fundamental moral questions, such as whether non-human animals deserve a “good life” and what this means in practice.</p>
<p>At the most fundamental level, Australians must ask themselves: should sentient, intelligent creatures have the freedom to access the outdoors? Or should they spend their lives in a barren cage so we can have the option of cheaper eggs? </p>
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Read more:
<a href="https://theconversation.com/australians-care-about-animals-but-we-dont-buy-ethical-meat-104394">Australians care about animals – but we don't buy ethical meat</a>
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<p class="fine-print"><em><span>Christine Parker received funding from the Australian Research Council to research “Regulating Food Labels: The Case of Free Range Food Products in Australia” (DP150102168) from 2015 to 2018. She is affiliated with the Australasian Animal Law Teachers and Researchers Association and the Animal Welfare Lawyers group.</span></em></p><p class="fine-print"><em><span>Lev Bromberg receives a Commonwealth Government Research Training Program Scholarship. He is affiliated with the Australasian Animal Law Teachers and Researchers Association.</span></em></p>Egg production standards are about more than just a happy compromise. Hens are sentient, intelligent beings. Like us, they deserve a good life.Christine Parker, Professor of Law, The University of MelbourneLev Bromberg, PhD Candidate, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.