My chickens live in a pole barn with outside freedom weather permitting. I currently have 3 Rhode Island Reds, 2 Silkies, 1 Barbed Rock hen & 2 Americanas. One of the reds is losing feathers like crazy. She looks pretty shabby. There are patches where her feathers were lost. I've been reading about molting, lice & mites to determine the cause. She acts normal, I've looked & dont really see anything but not sure of my findings. The molting pattern is in order except she did not lose any feathers on her head. Have had her @ a 1 1/2 years. This is first time I've seen this. Other chickens look fine thus far. Any info or suggestions would be greatly appreciated. Live in Chicago area so have Chicago weather. Thank you in advance.