before it was just a few chickens missing feathers...now it is even more. they are missing by the tail feathers. i have never seen this before. i have a few chix low in the pecking order whose butt feathers are gone. however, i have never seen it on top by the tail feathers. i know it is a sign of needing more protein. what are the best suggestions? i don't know who is doing it, is the hard part.