We are new at being chicken owners ande have 7 chickens all hens that are all the same age of about 10 months old. One of our Brahmas are loosing her feathers. I watched them today and none of them are picking on her but she is shivering cold. Could she be molting? We have never wormed our chickens and we give them free range during the day. I am just wondering why she is the only one loosing her feathers. What should I do? Thank you for the advise.