Bump on tail...why?

[CJW]

So, the other day, Kitty, one of my PWR was preening her tail, and I happened to look over. She had a small bump that she was cleaning near. I picked her up and checked on it...it isn't very large, maybe 1/4-1/3 inch tall and an 1/8 of an inch wide. It wasn't inflamed. It is near the end of her body, right over her spine. It has little holes in it. So, I picked up a couple other chickens, and they have them too, so I am thinking it is normal. (In one of my birds, feathers were growing out, but in others, the holes were vacant.) But my question is...What is it, and why is it there? I haven't seen it portrayed on any chicken anatomy diagrams. Could it be a scent gland or something?

I took a picture with my phone...(I never knew how hard it was to hold a chicken, a phone, and pull feathers back until now! LOL) I could try to get a side view tomorrow if anyone needs a better look.

 

[pgpoultry]

Don't worry it's the preening gland...oils the feathers....completely normal.

 

[Tala]

Yup, what they said. Oil gland. The chickens spread the oil from there to the rest of their feathers when they groom themselves.

 

[TeriyakiChicken]

I got stressed about my polish when I found a bump on her tail. I was going to post something but then I saw this post.

 

[CJW]

Thanks! I figured it was normal, but I didn't find anything on anatomy diagrams.