Please help. I have 26 Black Australorp hens and I have not noticed any aggression. My ladies are about a year old and have been losing feathers on their necks, bellies, backs and bottoms since February. I supplement their layer feed with BOSS so they should have enough protein. I have checked for mites and lice multiple times and have found nothing. They don't appear to be pecking each other as they only irritation on their skin seems to be just from sunburn. They are still laying well and are acting fine....They have constant access to layer feed and water. Weather here in central California is constantly changing with very wide temperature swings. Hope some of this info helps. Any ideas? Thanks for your time.