One of my NH hens has a strange bump at the base of her tail. It is shaped like the "fingers" on one of those shower massagers with the long handle. I'd say it's about 1/8" tall. It's all red, except at the very end, where it's yellow like a pimple that's about to pop. Prissy has pulled out quite a few feathers around it. I squeezed it gently and nothing happened (I was going to put antibiotic ointment on it) and Prissy didn't seem to feel any pain. I finally just sprayed it with some Wound-Kote so the others wouldn't bother it. She is eating and behaving very normally. Any ideas?