So at what age does a rooster become less of a breeder? I have two roosters who are 4 years old and since they have been 7 months old I have gotten fertile eggs from their hens. I am just wondering when I should start getting some new roo's to replace them. ALSO I was wondering this...In colder weather and less light days hens quick laying or slow their laying. Does a roo quit breeding? Does him mounting his hens and fertilizing their eggs less?