I have 4 chickens that are around 1 years old. My plymouth rock is going through a tough time right now. She started showing signs of molting in the middle of the summer, losing feathers around her neck (and no we don't have a rooster) and back area. I treated it as if she was molting by giving her extra protein and keeping an eye on her. She would lay strange shaped eggs with light pigmentation and rough spots on the bottom of the egg. About 2 months ago I started to notice she was scratching a lot and then thought it must be mites! I couldn't find any signs of mites but I used DE (as well as "Y-Tex Gardstar Garden & Poultry Insecticide" on them) in the coop and on her and the other chickens a few times a few weeks apart. She started to show some relief and grew a few tiny thin patches of feathers back where she had lost them and laid 1 or 2 good eggs.. but now i'm noticing her bald patch on her back looks very red and she was scratching again. She laid a soft egg and then hasn't laid since. Also as a side note, she hasn't been losing anymore feathers, its just the same bald patch on her neck and low back still. Any ideas or suggestions? Thank you!!