I have two one year old Americaunas. One is missing feathers around her neck and on top her head and she has a general rumpled look. I thought it might be from them not wanting to leave the coop in the winter and getting picked on. But it is not getting better and they have a large run, plus they get let out after 5 everyday to roam the backyard. Will the feathers grow back? And how long does it take?