Garlic is a very powerful antibiotic that doesn't harm good bacteria. Even with humans it can knock some stuff, like viruses, that won't get killed by the most potent antibiotics. I'm not sure but some chooks are supposed to be sensitive to it. I've never had that problem with my chooks but won't pooh-pooh it because it's a complicated world. But I use it as a rule, as much as the chooks want.
Pine tar, aka Stockholm tar, does amazing things to wounds, in the most messed up usually-fatal injuries, and kills pain almost instantly, and works rapidly. I've used it for pretty much everything without a single failure, no matter what caused the wound or how far the infection had gone. On a more gory note, I'm not squeamish, so I've stuck my pine-tarred fingers deep into wounds to make sure the tar got there. The animal actually found this a good thing since it killed the pain that was deeper in. Gross, I know, but he had gangrene. Pine tar killed the gangrene in one application but I gave him another the net day or so to make sure. I'm not sure about using anything caustic or acidic in wounds, I think you'd burn out the good healing cells as well as the infection, and the infection would recover quicker than the good cells. Everyone should have stockholm/pine tar in my opinion, for themselves as well as their animals, I've never seen anything heal so quickly and leave less of a scar.