Thanks Kim65 and goosedragon.
Kim, how dilute should the bleach water be? A quarter cup of bleach per gallon, or more dilute?
I did some reading around the forum and found reference to Neosporin many times, and also noted it was recommended in the various cooperative extension and university ag school poultry pages. So that's what I'll use. I also keep betadine in the first aid box and use it to clean wounds on my poultry. I'll definitely use it for this too.
Goosedragon, that handcleaner stuff is good to have around the barn (Softsoap and the rest). It has a compound called triclosan in it that is supposed to kill pretty much all the nasty varmints, but I don't know if that includes flu bugs. But in an emergency I've glopped it into scratches and other shallow wounds on poultry and used it to keep a hen's prolapsed vent clean while it healed.
Also... I always keep a bottle of penicillin g procaine, syringes and 18-gauge needles (also 25-gauge, but they're too small for the thick serum) hypos handy for emergencies, and I was thinking of injecting the "bumble" a couple of days first, before opening and draining. What are your thoughts?
The bumble formed almost on the side of the gander's toe, not quite under it, so it's easy to manipulate. If I could keep his foot clean enough, I'd remove it completely with a scalpel, but I'm afraid I'd be creating a bigger problem as it would probably require a couple of sutures.
Someone posted a photo of a neoprene "boot" they made for a duck to keep its foot clean after bumblefoot treatment, and I might try something like that and keep the gander in his barn stall on the deep litter for a week or more while he's recovering.