I noticed about 4 days ago, our only buff Orpington hen was missing a lot of feathers on her backside. She seemed to be acting normal so I picked her up to look and noticed a little yellow looking small worm on the bare spot. Picked her up the next day and never saw it again. I continue to keep an eye on her and she is getting very shy acting, but a few days ago she would still walk around the yard with the rest of the 10 hens and a rooster. Yesterday and today she will not leave the run, she doesn't sleep on the roost like she usually does. Instead she sleeps on the ground in a corner. I noticed the rooster and one other hen were picking on her the most. So I separated them this morning into a safe pen that is close to our big coop, I am going to watch for more dominant hens and separate them for a few days too if she continues to be picked on. I haven't noticed her eating or drinking and I try to dip her beak in water or food and it doesn't phase her. Not sure where to go from here so any help is appreciated!