What the hell...?
Anyway, I actually have a question about fertilized eggs. We recently got some eggs of different colors from a farmer in our neighborhood. One of the eggs so far had blood in it. More than specks, it was a noticeable amount swimming around with the yolk. I did notice they have a rooster roaming with the hens, so it probably is fertilized, right?
Ferocious - blood in the egg is not a sign of fertilization but a bleeding hen. Those little dots one sees in the yolk are also not a sign of fertilization, but little bits of blood from the hen. Lots of blood probably means a sick or dying hen. The sign of a developing chick is blood vessels growing around the yolk towards the empty space where a chick will have room to develop in the white - which is used more as a buffer to protect the egg and chick than anything and it is only a backup food source for the chick. The yolk btw is used for food by the growing chick and would not be affected by fertilization at all. Often you will see nothing at all for a week or maybe just some cloudiness when candling an egg. You wouldn't want to wait a week to check for fertilization before eating as the protein levels of eggs deteriorate over time so the most nutritious eggs you can get are the freshest. It's not like the chick is going to be developing in that egg without a mother hen or incubator so the more you wait to see if the egg is fertilized, the less nutritious the egg will be.
Here are some great pictures:
http://alistairpott.com/2008/06/02/photos-of-a-chicken-developing-inside-an-egg/It is more important to get an egg from chickens that are fed well (a sliding scale with really well being almost impossible to find - see my raw paleo chicken thread) than to get a fertilized egg. The whites might change a little with fertilization, but I don't like to eat raw egg whites whether fertilized or not as they taste wrong to eat for me. Therefore, I would much rather have just the egg yolks from my extremely well-fed hens and even eat a little bit of white here and there with them.
PaleoPhil has posted extensively on the subject and has proven to me that in the amount of eggs I eat (2-3 a day), even if I did eat the whites, I would have nothing to worry about re biotin absorption. I don't give the biotin issue much thought at all regarding my eating of eggs. If I liked the whites, I might just eat something else that is high in biotin to offset any possible but unproven issues. But generally - I prefer to trust my body and what it says than any outside source. My opinion is to find the best fed and freshest eggs first and foremost rather than giving too much importance to fertilization. Also, judge by the taste of the egg and how it makes your body feel rather than other undeterminable factors. Even if there is a rooster that does not necessarily mean that the egg is fertilized as it depends on how many hens there are to rooster and if the egg happens to come from the roosters favorite hen(s). Some rooster just choose one or two hens to fertilize constantly and leave the rest alone.
Again - I don't think the biotin issue has much value - but I feel like the food source and living conditions and freshness have massive value.