No real idea. I have known several guys in the birds that refused to use and did not believe in incubators. They said it ended up with a weaker bird.

I think, for no more than I know, the bird game evolves faster than the dogs. They will breed or get roosters off what is winning now. If they are breeding something that is linked to long ago, it has a direct link and a continual string of winners from yesteryear til today.

Dog people will use a set of papers to chase dead dogs and make futile attempts to re-create a dog from 30 years ago. Chickens not so much.

From that aspect I would say the chickens are bred earlier.

Secondly no one is doing the hens so they serve no other purpose but to breed. So that makes the younger ones more appealing.

That is about the jist of what I know.
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