I have 19 red Bantam hens. A few months ago I noticed they were losing their feathers under their vent and their chests. After some research I treated for mites. Then I started noticing that the hens were eating feathers, theirs and other hens. Did more research and learned they needed to free range to increase the protein in their diet. They are also eating about half of the eggs they lay everyday, I have oyster shell calcium available 24 hours day. Also, got 2 Maran roosters and put in with them, research showed this was supposed to help with the bullying. But after one day I had to remove the roosters because the hens had pecked them in front of their tail and had them bleeding. They all free range together and the roosters are breeding the hens but some hens fight with the roosters. Some of the hens are starting to regrow their feathers where others aren't and have no feathers now from chest to vent. Not sure what else to try, any suggestions welcome.