I have a bcm chick that hatched May 21 who has no feathers on his/her back. I've checked for mites and can't find any. They are still in the process of getting all their mature feathers in, but this one has the largest bald spot which includes most of the back. I can see the quills on the back, just no feathers. I don't see any injuries where other chicks may be picking on them but it is a possibility. Is this normal?