# How do we get edible chicken eggs **URL:** \ **Category:** Factual Questions\ **Created:** [May 25, 2006, 12:15pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154 "2006-05-25T12:15:13Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Skammer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skammer/32/143_2.png) [@Skammer](https://boards.straightdope.com/u/Skammer)\ **Post date:** [May 25, 2006, 4:22pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/21 "2006-05-25T16:22:31Z")
I remember as a kid (and it wasn’t _that_ long ago) when we would occasionally break open an egg from the supermarket and find that a chick had started to develop. It was pretty gross, especially if you got blood in your pancake mix or whatever. I haven’t seen it in years, though. ---
**Author:** ![RCGDC](https://avatars.discourse-cdn.com/v4/letter/r/c4cdca/32.png) [@RCGDC](https://boards.straightdope.com/u/RCGDC)\ **Post date:** [May 25, 2006, 4:39pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/22 "2006-05-25T16:39:14Z")
Is it the sperm or the mating behavior that determains if females lay? I recall reading that certain species of birds, Gulls for example, have a high rate of lesbianism. They will pair of in female - female couples and lay infertile eggs. They will care for them much as the same was female-male gulls do when their eggs, for some reason, don’t hatch. I remember reading this as the rate of lesbianism was high compared to the rate of male-male sexual behavior in Gulls and other birds ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [May 25, 2006, 6:11pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/23 "2006-05-25T18:11:54Z")
Back in the '50s, my aunt bought all her chickens and eggs from a local farm. One morning she was preparing breakfast and cracked an egg into the frying pan. It turned out to contain a live chick fetus (well, it was alive before hitting the frying pan). My aunt became immediately hysterical, fled the house in her bathrobe, and ran down the street, screaming. She must have knocked something over in the kitchen, because she started a rather serious house fire. To this day, she won’t eat eggs or anything containing eggs. ---
**Author:** ![Motorgirl](https://avatars.discourse-cdn.com/v4/letter/m/e36b37/32.png) [@Motorgirl](https://boards.straightdope.com/u/Motorgirl)\ **Post date:** [May 25, 2006, 6:31pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/24 "2006-05-25T18:31:15Z")
> [@Freddy the Pig](#): > > At what point does a fertilized, incubated egg become inedible? I assume that people started eating eggs by robbing the nests of wild birds (or reptiles or, in Australia, mammals). But I don’t know any culture that enjoys eating _embryos_; people want the yolk and the white. Is the trick in wild-egg eating to get the egg as soon as possible after it’s laid? When does it become inedible? Never. Behold… [balut](http://www.mcsweeneys.net/links/dolgin/27duckembryos.html) ---
**Author:** ![RickG](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rickg/32/5174_2.png) [@RickG](https://boards.straightdope.com/u/RickG)\ **Post date:** [May 25, 2006, 7:03pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/25 "2006-05-25T19:03:54Z")
> [@panache45](#): > > Back in the '50s, my aunt bought all her chickens and eggs from a local farm. One morning she was preparing breakfast and cracked an egg into the frying pan. It turned out to contain a live chick fetus… For those of us who observe _kashrut_ (Jewish dietary laws), eggs are considered to be neither meat nor dairy, and so may be eaten with either one. However, if the egg contains a blood spot (or a developed embryo :eek: ), it becomes meat. If you put such an egg into some dish, that entire dish becomes meat, and so cannot be eaten with dairy (or if the recipe has dairy in it, the whole mixture becomes forbidden). So the common practice is to have a small separate bowl for breaking the eggs. Break the egg into the bowl, check for blood spots, and, if there aren’t any, transfer the egg into the recipe or the frying pan. Even though, with modern egg processing and quality control, finding blood spots is exceedingly rare, and the spots aren’t from an embryo, anyway–they’re just from microbleeding in the chicken’s reproductive tract, AFAIK–I still break my eggs one at a time into a small bowl before using them. Rick ---
**Author:** ![Carol\_the\_Impaler](https://avatars.discourse-cdn.com/v4/letter/c/6a8cbe/32.png) [@Carol\_the\_Impaler](https://boards.straightdope.com/u/Carol_the_Impaler)\ **Post date:** [May 25, 2006, 7:15pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/26 "2006-05-25T19:15:32Z")
My mother (raised Presbyterian, now converted Catholic) taught me to do this, as well. Religious restrictions aside, why is a blood spot in an egg a bad thing? ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [May 25, 2006, 8:25pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/27 "2006-05-25T20:25:49Z")
> [@Freddy the Pig](#): > > In the case of a wild bird, what does the egg look like at the point when it’s fertilized by the sperm? I had always pictured that the bird produces a small egg cell, not unlike a human, and then, _if it’s fertilized_, develops it into the big, yummy, yolky thing that we buy at Jewel. But it sounds from your post like big-egg development starts with courtship. How far does it get before mating and fertilization? Does the sperm have to penetrate the egg shell? 😕 Yeah, when and how does the sperm penetrate the egg. For some reason I have it in my head that the egg is penetrable as it emerges and that’s when it would be fertilized?? ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 25, 2006, 8:42pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/28 "2006-05-25T20:42:21Z")
> [@gigi](#): > > Yeah, when and how does the sperm penetrate the egg. For some reason I have it in my head that the egg is penetrable as it emerges and that’s when it would be fertilized?? I’m sure fertilisation happens before the shell is secreted; if you ever have the pleasure of buying a fowl that has just been slaughtered and you have to deal with the feathers and innards for yourself, it’s not uncommon to find a number of eggs in various stages of development all queued up in the reproductive parts; sometimes these will have a sort of half-formed leathery shell; others might be naked egg-like masses, or may just appear to be nothing more than yolks. ---
**Author:** ![Freddy\_the\_Pig](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Freddy\_the\_Pig](https://boards.straightdope.com/u/Freddy_the_Pig)\ **Post date:** [May 25, 2006, 8:43pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/29 "2006-05-25T20:43:00Z")
I was hoping **Colibri** would post again, but maybe I can kind of answer my own question. Apparently the sequence is (a) ovum and yolk produced inside female; (b) fertilization; © egg white and eggshell added around yolk; (d) egg laying. Sex can occur either before or after (a), because the female can retain the sperm inside her body for a fairly long time. Here’s what surprised me: Apparently, in wild birds, © and (d) take place regardless of whether (b) took place. As **Colibri** said, once the ovum gets produced, it gets built into an egg and laid whether the _bird_ got laid or not. So the “defect” in domestic fowl isn’t that they lay unfertilized eggs–_any_ bird will do that–but that they produce so dang _many_ of them, at all times of year and in response to little stimulus (bright light) or no stimulus at all. Very interesting. You would think that birds would have evolved some way to “know” whether their ova got fertilized or not, because an awful lot of food and even incubation time gets wasted on producing dud eggs. Perhaps in the wild it’s so easy for hens to get laid that failure to fertilize isn’t that big of a problem. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 25, 2006, 8:49pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/30 "2006-05-25T20:49:38Z")
> [@Freddy the Pig](#): > > I assume that people started eating eggs by robbing the nests of wild birds (or reptiles or, in Australia, mammals). But I don’t know any culture that enjoys eating _embryos_; people want the yolk and the white. Is the trick in wild-egg eating to get the egg as soon as possible after it’s laid? I think that such foraging proto-cultures would not be nearly so picky as we are; given that any source of food would be quite valuable; if they didn’t mind eating invertebrates and all bodily parts of vertebrates they hunted, i can’t imagine they’d be too fussy about their eggs. in any case, in the wild, there is often quite a window of opportunity between eggs being laid in a nest and when the clutch is complete and the hen begins incubation; raiding the nest at any point within that time is probably going to yield eggs with no discernible embryo. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 25, 2006, 8:53pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/31 "2006-05-25T20:53:05Z")
> [@Freddy the Pig](#): > > You would think that birds would have evolved some way to “know” whether their ova got fertilized or not, because an awful lot of food and even incubation time gets wasted on producing dud eggs. I think it’s pretty much a non-issue in the wild; mating and laying fertile eggs is very mught the norm; not many birds decide to put it off in favour of a career in marketing. > [@](#): > > Perhaps in the wild it’s so easy for hens to get laid that failure to fertilize isn’t that big of a problem. Yes. Although not ‘easy’ it’s absolutely the default behaviour. ---
**Author:** ![flight](https://avatars.discourse-cdn.com/v4/letter/f/bbce88/32.png) [@flight](https://boards.straightdope.com/u/flight)\ **Post date:** [May 25, 2006, 9:48pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/32 "2006-05-25T21:48:07Z")
> [@gigi](#): > > Yeah, when and how does the sperm penetrate the egg. For some reason I have it in my head that the egg is penetrable as it emerges and that’s when it would be fertilized?? The egg is hard when it is layed. No idea about when fertilization occurs relative to laying. ---
**Author:** ![Tabula\_Rasa](https://avatars.discourse-cdn.com/v4/letter/t/a9adbd/32.png) [@Tabula\_Rasa](https://boards.straightdope.com/u/Tabula_Rasa)\ **Post date:** [May 25, 2006, 11:37pm UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/33 "2006-05-25T23:37:12Z")
> [@RickG](#): > > For those of us who observe _kashrut_ (Jewish dietary laws), eggs are considered to be neither meat nor dairy, and so may be eaten with either one. However, if the egg contains a blood spot (or a developed embryo :eek: ), it becomes meat. If you put such an egg into some dish, that entire dish becomes meat, and so cannot be eaten with dairy (or if the recipe has dairy in it, the whole mixture becomes forbidden). > > So the common practice is to have a small separate bowl for breaking the eggs. Break the egg into the bowl, check for blood spots, and, if there aren’t any, transfer the egg into the recipe or the frying pan. Even though, with modern egg processing and quality control, finding blood spots is exceedingly rare, and the spots aren’t from an embryo, anyway–they’re just from microbleeding in the chicken’s reproductive tract, AFAIK–I still break my eggs one at a time into a small bowl before using them. > > Rick I grew up about as unchurched (or un-house-of-worshiped) as can be, and my mother taught me to do the same thing – break each egg individually into a separate bowl to check it for defects or ooky things and to catch any bits of shell that got into it. She also kept a strong light in the kitchen and, especially when we bought country eggs, we held them up to the light (“candled” them) to be sure we could see the round yolk. It was rare, but I saw a few fetal beaks and toes through the shells. We threw those eggs out. I have continued to do this and, twice in twenty years, have found semi-commercial eggs that did not pass muster. Candling can’t identify the tiny-point-of-blood eggs, but it can save one from opening a feathers-and-all egg. Tabby ---
**Author:** ![picunurse](https://avatars.discourse-cdn.com/v4/letter/p/7bcc69/32.png) [@picunurse](https://boards.straightdope.com/u/picunurse)\ **Post date:** [May 26, 2006, 12:03am UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/34 "2006-05-26T00:03:35Z")
> [@gigi](#): > > Yeah, when and how does the sperm penetrate the egg. For some reason I have it in my head that the egg is penetrable as it emerges and that’s when it would be fertilized?? When the bird egg leaves the ovary, The shell is just a semi-permeable membrane that holds it all together. The sperm is able to penetrate the membrane. The shell is still soft when layed, it hardens immediately when air hits it. ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [May 26, 2006, 12:42am UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/35 "2006-05-26T00:42:20Z")
> [@Freddy the Pig](#): > > At what point does a fertilized, incubated egg become inedible? I think that depends entirely on how hungry you are. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [May 26, 2006, 3:55am UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/36 "2006-05-26T03:55:06Z")
> [@Freddy the Pig](#): > > I was hoping **Colibri** would post again, but maybe I can kind of answer my own question. Apparently the sequence is (a) ovum and yolk produced inside female; (b) fertilization; (c) egg white and eggshell added around yolk; (d) egg laying. Sex can occur either before or after (a), because the female can retain the sperm inside her body for a fairly long time. This is correct. The ovum (which mostly consists of yolk along with a small germinal disk which will eventually produce the embryo) is essentially full sized when it is fertilized inside the oviduct. The white of the egg and the shell is added subsequently. See [here](http://www.enchantedlearning.com/subjects/birds/info/chicken/egg.shtml) for a diagram. [Here’s](http://www.hhmi.org/cgi-bin/askascientist/highlight.pl?kw=&file=answers%2Fgeneral%2Fans_023.html) a bit more detail on the process. > [@picunurse](#): > > The shell is just a semi-permeable membrane that holds it all together. The sperm is able to penetrate the membrane. > The shell is still soft when layed, it hardens immediately when air hits it. No; the shell is not present in any form when the egg is fertilized. Being made of calcite, it is hard before the egg is layed. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [May 26, 2006, 4:14am UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/37 "2006-05-26T04:14:11Z")
> [@Colibri](#): > > Being made of calcite, it is hard before the egg is layed. I should clarify: while it is somewhat softer when layed, it is not membranous, as I thought was implied. ---
**Author:** ![Hunter\_Hawk](https://avatars.discourse-cdn.com/v4/letter/h/50afbb/32.png) [@Hunter\_Hawk](https://boards.straightdope.com/u/Hunter_Hawk)\ **Post date:** [May 26, 2006, 4:24am UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/38 "2006-05-26T04:24:56Z")
> [@Colibri](#): > > I should clarify: while it is somewhat softer when layed, it is not membranous, as I thought was implied. With the occasional exception, of course. Oftentimes young birds that are old enough to start laying but still aren’t fully mature will lay a few eggs with soft shells. ---
**Author:** ![David\_Simmons](https://avatars.discourse-cdn.com/v4/letter/d/9de053/32.png) [@David\_Simmons](https://boards.straightdope.com/u/David_Simmons)\ **Post date:** [May 27, 2006, 4:09am UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/39 "2006-05-27T04:09:23Z")
> [@Hunter Hawk](#): > > With the occasional exception, of course. Oftentimes young birds that are old enough to start laying but still aren’t fully mature will lay a few eggs with soft shells. As will any hen lacking sufficient calcium. A co-worker of mine, a city boy, and his wife, a city girl, decided to raise chickens for the eggs. After awhile he asked me what was wrong with his hens as all the egg shells were soft. I told him to get some oyster shell feed at the feed store and in the future buy chicken feed with calcium added. One of his horses stepped on a chicken and broke its leg. He asked me how to put the poor thing out of its misery. “Cut its head off.” Well, he didn’t want to so I took my butcher knife and did it for him. Such agonizing you never saw as that which he went through. I think they finally gave up on chicken raising as too brutal. ---
**Author:** ![crowmanyclouds](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crowmanyclouds/32/19884_2.png) [@crowmanyclouds](https://boards.straightdope.com/u/crowmanyclouds)\ **Post date:** [May 27, 2006, 10:40am UTC](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154/40 "2006-05-27T10:40:35Z")
> [@AskNott](#): > > …That stringy part attached to the yolk at each end of the egg… [Chalaza](http://www.aeb.org/LearnMore/Eggcyclopedia/C.htm#Chalaza): Ropey strands of egg white which anchor the yolk in place in the center of the thick white. They are neither imperfections nor beginning embryos. The more prominent the chalazae, the fresher the egg… CMC fnord! [Previous page](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154.md?page=1) [Next page](https://boards.straightdope.com/t/how-do-we-get-edible-chicken-eggs/358154.md?page=3)