HI, I am new to hens. I noticed today that one of our 3.5 month old hens is missing quite a few feathers on her back and the skin is covered wit light colored scabs. Either new feathers are coming in or they've been plucked out, not sure which. Also, not sure how long this has been going on. She seems fine, is eating well, they have enough food and water, there is not much visible blood except for a small drop near the base of a feather. I looked at the rest of her skin for lice or mites. I am not sure if I'd know them if I saw them, but she doesn't appear to have any. Not sure if she might be pecking herself or if the others are. I haven't seen any action, just the result. Any ideas? Thanks!