What is wrong with my chicken’s back?

Question:

My chicken has something going on with her back. She is the last to lay eggs so maybe the runt. I witness a time when another pinned her down and pecked her. What do you think might be wrong with her back?

Answer:

Your hen has either been mounted by an aggressive rooster or is being pecked on by other chickens. If she is the only one with missing feathers, move her to an isolated area and feed and water separately for a week or two. Then reintroduce her to the flock. If you think it is an aggressive rooster you can either remove him or make capes or saddles for the hens that are affected.