Hello we have nine hens; 4 Bramas and 5 Plymouth Rocks. They are all just over one year old. Last fall the Plymouth started losing feathers on their butts. My wife and I thought they were molting. Fall turned into winter and winter has now turned to Spring. The feather situation on the Plymouth seemed to get a little bit worse in winter. But over the last several weeks it seems to be much worse. It's no longer just their butts but their sides and it's creeping under their wings. We have examined the chickens for mites or lice and there's none visible to the naked eye. We've wiped their roosting bars at night and no signs of red marks. It does not appear to really be affecting the bramas. The grey ladies are the Plymouths and the white and black are the bramas. My wife made an aloe sulfur herb paste and applied. I think that made it worse. Although I think that's because the hens pecked their own feathers because the paste was bothering them. Our guess is depluming mites but not sure how to treat. Any ideas?