My cat has a wound on his tail. We don’t know where the wound came from, but it looks like a scratch, it’s not very big, and we suspect it came from a mean neighborhood cat.

However, it has a weird strand of something coming out of it that has me worried. It’s thin, about 2.5 inches / 6 cm long, roughly tan colored except in a few places where it’s dark and more red, and about halfway down its length it becomes very thin, kind of like a hair. It does seem to be affixed to his tail, though I’m not sure if it’s actually coming out of the wound.

Here’s an album with a few pictures of it: http://imgur.com/a/bTck4

Touching it is obviously uncomfortable for my cat. Occasionally he’ll lick it, and I’ve seen him chewing at it a few times as though he’s trying to get rid of it. Other than that, I see no change in his behavior. His tail still has its full range of movement.

What is this thing? Is it serious enough that we should take him to a vet?