So I got a roo and a hen Tuesday, and he has bred with most of my other hens a few times this week. How long does it take for the eggs being layed to be fertile. When the hen that came with him starts laying again, I assume her eggs will fertile. It's my hens that I'm not sure about. My roo was killed today, and I want to try to hatch some of my hens' eggs, but don't want to start collecting too soon. Make sense?