Same thing here. They seem fine but bare ventsMy hens will spend some amount of time sitting on the egg, but I don't know exactly how long they did it. I still am trying to figure out why their butts were like that. They looked fine otherwise and acted healthy, ate well, etc. I am still trying figure out what was going on. I dusted them with DE powder for mites, but that didn't seem to make much of a difference.
She might have lice. They like it around the vent and when they tickle, she pecks at them, taking feathers out. May be.If you are talking about feathers around the vent, a bird doesn't pluck those. They will pluck breast feathers but only if they are broody. Have your birds been sitting on eggs this summer?