I just purchased 10 3-week old chicks from a local Ma & Pa hardware store. Two Buff Orpingtons, which were housed in one pen, and 8 Ameraucunas, which were housed in a different pen. Almost all of the Ameraucunas have feathers missing on their backs...bald spots. Could this be from them pecking each other? Does not seem like disease. Should I treat in some way??