Ive got this hen that doesnt have feathers on her back and part of her wings. Its been like this for awhile since last summer. I do no not have any roos. No lice or mites. I have one other hen that is bare on her wings. Just a spot. This hen is prolly 2 years old. Acts normal. They eat table scaps with corn and scratch. Have access to oyster shell and sand. They arent crowded and they have lots of room to roam. Ive tried puttin blue kote on her but still no feathers. I havent seen any feather eating. I do have one hen that decided she would be a roo but i have 15 hens besided her/him lol. So does anyone have any ides how i can help her grow feathers back?