How long after a hen lays her eggs does it take the rooster to fertilize it?
Chickens and other birds use internal fertilization. That is, the hen and rooster mate, and then the hen produces eggs. Once an egg has been laid, it can not be fertilized. It either already contains an embryo or it doesn’t. Hens will lay eggs whether they are mated with a rooster or not. For more information see the factsheet on the anatomy and physiology of reproductive system of the female chicken.