We have about 40 chickens all this years chicks. we have lost 3 golden sexlink hen in the post two weeks.No sign of anything no bleed just found them in the yard dead.Today my husband saw the rooster on top of her he looked back and the hen was dead there were some feathers where he pulled out of her. We have 4 rooster and the chickens all are free range .We have amber links, RR and golden sexlinks . Any ideas what going on with the hens do you think it is the roosters killing them .Please help