I'm suspicious of the rooster cause she screams when he chases her...normally I just see him mount her and then gets off so I can't imagine it being caused by him. They are both 10 months old. I have two other chickens but one is very old so I kind of keep her away from him during the day. But I really don't think it is him...I mean she is very bald in this spot with two gashes that I sprayed Vetericyn on. I had to take a picture of her with one hand so it's not the best but does anyone know what is causing it. I am including two pics although not the best like I said.