19 year old Morgan gelding. Liver chestnut (not gray). On his flank is a small, tall as a pencil eraser and maybe just a bit wider than that, hard , under the skin bump. Hair is still normal on it. No touchiness when I push or prod. Doesn’t seem to bother him at all. It’s been there for a bit, I first thought it was a horsefly bite but it hasn’t gone down - I don’t think it’s gotten any larger since I’ve noticed it either. I’ve never dealt with any sort of odd skin lumps so I really have no idea. I’m of the mind to let it go until the next regular vet visit if there’s no change?
I, personally, would let it wait until your regular vet visit. My horse is constantly coming in with mysterious bumps and bruises and cuts that don’t ever seem to bother him.
This specific instance sounds like nothing to worry about. My guy gets bumps like that from “friendly” kicks in the pasture. They never hurt when I press on them.
Long story short, I would just wait unless something changes in a bad way.