Could she be stressed by the fact that she is separated from the other hens?
If she is a very social bird then she may be missing her friends. Is it possible for you to let her see the others during the day whilst still keeping her separated - by putting her cage in the coop or run for a while, or keeping her in a run adjacent to the other birds for example?
If she is a very social bird then she may be missing her friends. Is it possible for you to let her see the others during the day whilst still keeping her separated - by putting her cage in the coop or run for a while, or keeping her in a run adjacent to the other birds for example?