Did you ever figure out what this was? Our chicken had a big bald spot on her back and her wing feathers were snapped. I thought it was just bullying or bad genetics not letting her grow her feathers back after molting. She had started to limp and when I checked her out, she had this huge black scab (like the one in the photo) under her wing. She had a very big appetite however. Has anyone figured this out?I also notice this was two years ago! But...my chicken has something like this in her back that seems rock hard. She is also limping greatly about the same time I noticed it! any advice?