(I forgot to ask this) do they have a buddy.? I've dealt with two abscesses so far and I think mine are from a bit too hard of a play bite.!
Are they neutered.? If not I would recommend doing so if they are fighting. Do they draw blood on each other or is it just play.? All my rats are young so they are still learning. If you can flush the wound a bit that may help it heal faster and if he starts to seem off or the hole doesn't look better soon I would take him to the vet.! My first abscess encounter I got her on antibiotics but the second we didn't give any antibiotics as it was already healing so we kept it clean and now you can't even tell.!Yes! He has two. His brother and another male. The other male is kind of the alpha of the two. There is lots of fighting in the cage.