My wonderful hen that I bought at fair this year has been having some problems with a very irritated butt by the vent hole. The spot of irritation is almost a perfect circle. She isn't low on the totem pole but I have noticed my other hens picking on her back not bottom so we are pretty sure that is not the problem. I have also noticed her butt scooting so it could possibly be allergies. Please get back to me ASAP, I don't know how much longer she can hang in there.