this has been going on for many months. Molting is not a factor. They are just now two years old. Everything is the same and I am stumped. We keep their coop and pen clean, change water daily. I don't know who is laying and who is not. One of the hens however has lost feathers from her comb back about 1 1/2 inches. It has been this way for a while as well. We do treat them holistically for mites and we treat their coop as well. I would appreciate any feedback.