I think something is going on with my 15 month austerlorp hen. The feathers at the base of her tail got worn off due to the excessive mating of the rooster (he's now gone - due to other reasons, too.) but they have not returned and the skin remains red and the rest of her skin under her feathers is very white/yellow. Doesn't look healthy. Now she seems to be developing black spots on her comb. I have checked her for lice, even dusted her, the coop and the others with DE. No change. Any ideas?