So LindaB220 asked me if I knew where to find the study she read that discussed the influences of maternal nutrition on gender selection of poultry offspring ... I don't. I could start googling different interesting/unique combinations of key words and phrases, but as I'm not the one who read the study I don't actually know what interesting/unique combinations of keywords and phrases might have been used in that particular article that could help a person google it more efficiently.
I did do some test googling and found this one study involving some type of seagull, I think, that suggests there is a bias towards female hatchlings in less-well-nourished mother gulls ... "Experimental demonstration that offspring sex ratio varies with maternal condition"
http://www.pnas.org/content/96/2/570.full
The idea of that study is that male hatchlings are bigger, and need to grow more. So more nutrients in the eggs, and somewhat larger eggs, might shift a bias towards the opportunity for more male hatchlings ... and the study achieved "enhanced" eggs by offering the potential mothers baked eggs ... and they did note an increase in egg size and an increase in male offspring.
There isn't a lot of science, I don't think, about feeding eggs to chickens, probably because eggs are an important product of the poultry industry so poultry farmers tend to prefer to sell/hatch eggs rather than feed them back to the birds. My instincts tell me eggs are great nutrition for birds, not due to the exact protein percentage of un-dehydrated eggs, but because of the nutritional profile of the eggs. I offer my breeders and babies scrambled eggs. I've usually got plenty of "funky" eggs to use for this purpose.