I have three red sex-links that are just a year old. One of them has lost a lot of feathers, mostly on her neck and belly. Yesterday, I noticed that several spots on her belly are completely bare and look red and irritated. She still lays almost every day. Initially, I thought she was being picked by the others as she is the low chicken. They have been confined to their coop and stationary run for the winter while there is snow on the ground. so they have not gotten their usual volume of grass and bugs. I have been supplementing with mealworms, scratch, and green scraps such as kale, in addition to their regular layer pellets. I am confused by the new bare patches on her belly as I didn't expect her to be picked there by the others. Is it possible that she is molting? I have seen some feathers in the coop, but not many. She would not cooperate for a picture of her belly, but here is a picture of her neck. You can also see where she has lost some feathers on her rump, her back looks fine though. I have checked for mites and don't see any. Thank you for the help.