I have three Jersey Giant hens and two roos that are nine months old. The hens started laying at about six months and have been laying steadily since. I have tried using each roo with them but so far have not seen any sign of a fertilized egg. I also have not seen the roos doing their job either. Is it possible they are still too young? I have some eggs in the bator to check for fertility but they are rather dark and it is hard to see anything definite. Help! Suggestions appreciated.