Several of my girls have patches like this. The skin is sometimes bright red other times it looks like their normal skin. I haven't seen any external parasites. I haven't noticed any unusual aggressive behaviors or feather plucking. None of my girls act broody. I allow the to free range for a few hours every day when I am home from work and all day on the weekends. They are given a quality organic food, kale, and a few handfuls of scratch in the mornings. I have only had chickens for a little over a year and I worry that I've missed something important. Please help soothe this worried chicken Mama's fears?