When does a Polish Bantam become a fertile roo? My Afroman is 10 months old, But still has not produced a fertile egg. He's got 13 chickens all to himself and I've collected eggs everyday from the ladies set them to the bator and still yet to find a fertile one by the 4th day. Is something wrong with my roo. He tries alot. My chickens are also 10 months old and are all Rhode Island Red and 1 Americana. All my chickens have been laying for a while now.