My little Bertie cat was " got-at " by a fox a couple of years back. I'd heard a commotion in the garden and knew the sound of the fox and also Bertie putting up a fight. Anyway the cat's hind leg had been caught as it had a gash in it so I bathed it and put germolene on it as it wouldn't harm if he licked it off. Fortunately the cat didn't suffer any ill-effects so there was no need for a visit to the vet.
The fox had obviously been after the fleece cover that's in the cat kennel outside ( for an old stray tomcat ) and had dragged it up the garden and Bertie objected !