We've had our chickens about a year ( we have 10 Isa Browns...no rooster). They have a large coop and a run. We noticed this winter that one of the chickens comb turned a little black and we figured it had gotten frost bite. For the past few weeks, we've noticed that the other 9 chickens pick on her and peck at her comb. It's gotten sore and she's missing feathers on her head. They don't allow her to eat or drink and she stays on the roost all day. Once she comes down, they attack her. We've been letting her out when we get home from work so she can free range and eat. When we put her back in the pin....they attack until she's able to get to the roost. I would figure the pecking order had been established long ago. Any ideas on what's going on and what we can do to help her out? We've though about leaving her out full time until her comb heals up but we're not sure. Thanks for your help!