Hi I have 19 hens 1 year old and 1 rooster. About 6 months ago one of my hens cut her head on something. I treated it with antibiotic cream and it healed nicely and she seems normal, but the other chickens and rooster pick on her. Would anyone know the reason why? Also some of my chickens have lost feathers on their backs and they do not seem to grow back.Thanks for any Info.