How old does a rooster have to be not to breed I have a silkie rooster he maybe 4 year old with a silkie hen and the eggs are all infertile last year she would set but none of the eggs would hatch. I put a younger hen with him same thing his spurs or about 3 inch long could they get in the way of him breeding he will mount the hens.I had him in a pen with more silkie rooster before he is the only one I have now .DK