Just a thought that I cannot seem to find much info about. If a chicken like a leghorn or commercial layer is eating only about 110grams of feed per day and yet can pretty much produce an egg a day, then surely the nutritious quality or density per gram of egg cannot be as good as say a welsummer which will produce less eggs and yet eat more feed. More feed and therefore nutrition has gone into the welsummer's egg as it took the feed from about 30 hours to produce instead of the the leghorns egg which took the feed from only about 25 hours worth of eating? So is there any differecne in the actual egg health or nutritious quality/density per gram of egg depending on breed and the amount of food they eat. I just can't see how the nutritious quality of a leghorn (or commercial layer) egg can be the same as that of other breeds (similar in size or bigger size like delaware) for so much less food consumed.
I think you'll find nutrition wise that it matters more what the bird is eating than the quantity it is eating. Plus the use that the bird has been bred for makes a difference on how much feed is needed to produce one egg. Leghorns are bred to lay eggs, if you compare it to an egg from a bird bred to be a meat bird then it will probably take more feed for the meat bird to produce an egg. This is because the egg bird will have in general less body mass to support nutritionally than a nice big fat meat bird.
