My wife lost one of her girls today. She was a leghorn, about 18 months old. She showed signs of illness yesterday: dirty, smelly rear end; droopy, faded crown; weak, slow, hanging head. My wife gave her a bath, trimmed her back feathers then put her in isolation with fresh food and water. We did a little research yesterday and was thinking maybe prolapse. Today "sugar lips" didn't do much moving then died around noon. About 10 days ago we added 6 new birds to the flock. Without first researching, we kept them separate from the rest for a couple of days (two "rooms" in the coop) then let them meet and roost together (I know, I should have isolated them for a while). The farm we got the new girls from had about 40 hens and one mean *** rooster. Many of the hens were missing feathers on their backs but none appeared sick or injured. None of the other hens are showing any signs of illness. I know there are a thousand things it could be but wanted to get a conversation going to get some ideas. Should I get something and pre-treat for cocci? Thanks!