I have 5 chickens, 2 Americuanas, 3 RR, The are pecking each others rear ends to the point that there are no feathers left. I have tried everything that has been mentioned on this board, more protein, free ranging, pine tar, blue kote etc. My last effort will be to isolate them one at a time until their feathers grow back, then see what happens. My question is how long should I isolate them. Will the feathers grow back and how long does that take. Their rear ends are right down to the skin. Pretty disturbing to see. If this doesn't work I may have to cull them and start again. Any help would be appreciated.