I had a young pullet get injured that bad by a young cockerel and his favorite pullet. They ganged up on her and completely scalped her. I nursed her back to health and she was bald for a long time. But, when she went through her first molt almost all the feathers grew back in. I was so surprised. One thing I did so she wouldn't be pecked at is keep blu-kote on her until she had feathers. Chickens are attracted to red, so there was a high likelihood that even though the cockerel and his besty were removed the other pullets would pick at her.