I have a Black Silkie rooster in with 4 white and 1 Black silke hens. I hatched 7 chicks from him about a month ago, This batch of 9 eggs under two hens candled completely empty at 2 weeks. All duds. Has he gone infertile? Is it the Alabama summer Heat? We have seen him mating with all 5 hens. He is only a year old and not molting. Ideas?