My hen has gradually been losing feathers on her neck for about 6-12 months. I originally thought they were getting pulled out by my one other hen as I saw her do it once but as it gets more bare I'm not so sure. I don't see her pulling at her feathers enough to explain this (only once) and I spend a decent amount of time watching them. Sometimes her skin is white and other times red & irritated looking. Has anyone seen this before?