Tea tree oil with deep wounds and taking oral sodium chlorite (5 drops citric acid to 1 drop MMS solution) and I'd start with around 3 drops MMS every couple of hours and see how he feels.
After about an hour or so I'd take an activated charcoal to absorb the things that get killed and move it safely out of the system. And then keep up this routine, keeping a very, very close eye on the wound.
I get very nervous about tetanus as lock jaw is so stinkin' scary!
I also know that if you have Turmeric (it's a spice and I get mine from www.swansonvitamins.com in capsules, but you'll find it in the spice section in bulk) I'd take that, too, as it greatly BOOSTS the immune system. It's very orangey-yellow.
HTH and gentlest hugs,
Pamela, Type 3, strong secondary Type 4
"that through his death he might bring to nothing the one having the means to cause death, that is, the Devil;" Hebrews 2:14
"As the last enemy, death is to be brought to nothing." 1 Corinthians 15:26