This is Patty my 7 month old black australorp. Her feathers have been looking like this for about 2 or 3 weeks, I have 5 black australorps and their feathers all kind of look like this now but hers are the worst. I looked over them and I didn't see any signs of lice or mites. I have 6 other chickens who are different breeds and their feathers look fine. Is it normal or should I be concerned?