I have one hen that has lost her neck feathers. There is no sign of mites, or sores on her neck. She is afraid of people and has been standoffish of the other chickens. She has also lost a few tail feathers. She will be a year old in March. Someone said a cat or a skunk may have reached through the chicken wire and hurt her but I don't see any injury or blood. We have 10 other chickens that all seem fine. Does anyone have any idea about this?