Today one of my hens was sitting on the roof of the coop, trying to get away from the other hens. Shes been like that all day. I went out to investigate and saw that her feathers were missing around her vent and the vent and picked area was bloody. There was blood on the roof too. Shes the skapegoat of the flock and i think the other chickens are picking on her. What should i do? Should i isolate her? Should i remiove her from the flock? Any help would be much appreciated!