My bantam hen cannot sit on her perch and has been sleeping on the floor of the coop. She sits down in the run and occassionally gets up to walk. When she's walking, one leg gives out and she's sits down again. She has trouble getting in and out of the coop. I have isolated her because I thought she might have Mercks. She has lost quite a few feathers and you can still see the shafts on her. Her appitite is great. This has been going on for 3 weeks. She's been in isolation for 2 weeks. She's walking better now but I don't know if I should return her to the coop with the other chickens. She is a golden sebright and is 3 1/2 years old.