I have 12 chickens total in my flock. They are 24 weeks old. My Golden Laced Wyandottes have been pulling feathers out underneath the wings on their thighs. The other ones go after the bare skin and peck until they bleed!! Its awful They have large wounds from the others pecking at them. I have treated the coop with DE, and the wounds with BlueKote. What causes this? Both of the chickens have wounds in the exact same place on both sides. They are eating and drinking fine and still laying. Is there anything I can do??? I'm at a loss and don't know what else to do. Any advice would be extremely appreciated!!