We've had our chicks for about two weeks now and they've been doing great. However, over the last couple of days I've noticed one of our Golden Buffs (Red Comets?) isn't looking so great. She's missing a lot of fluff around her neck and it looks matted and picked at. I've noticed her picking at the area and one of the other chickens as well, but it wasn't "violent" and there isn't any scarring or bleeding. Should I separate her from the others or does she need some sort of medication? Any advice would be appreciated.