The wound was quite deep and a bit of pus oozed from it when I pressed on it. Yes, the Russian allowed me to.
Being Saturday, my regular vet doesn't work, so I thought I'd try to nurse the wound myself.
I washed it with saline, then applied iodine and the Wound Protector ("Happy Bum Gel").
I managed to do that about five times yesterday. The Russian was a complete pussy-cat and allowed it all. I also gave him Vetri DMG.
This morning, I checked and the wound looks much, much drier and better. There is still a tiny bit of pus, though.
I repeated the procedure, but he put up a bit of a fight and struggled to get away.
This usually means he is much better (and thinks he doesn't need the first aid anymore).
Our disclaimer holds. Please consult your vet if your pet has any injury.