One of my BO hens has a problem with poop getting stuck in the feathers under her vent. I've given her a bath in the past, but it's built up again, and yesterday I noticed she'd managed to pull a lot of the dried stuff off along with feathers leaving a pink raw looking area. My fault for not getting her to a bath again right away. She's fluffy enough, that I don't think the others noticed and pecked at her. Why though does this keep happening? None of what I've read indicates it's a disease problem. No one else in the flock has a similar problem.