I deal with horses in my spare time, and it’s fairly common for them to step on something that injures a foot (OK, no barbs that it’s really a toe–I know).
The common practice is to pull or cut out the foreign object (if it is still lodged in) and soak the foot in Epsom salts–because it helps “draw out any infection.”
I have a couple of ideas on this:
People have been known to soak their feet, so it must be good for a horse, too. (But I think most of the therapeutic value in foot-soaking for people is that the warm water feels good–not because of the salts)
The salinity does discourage bacteria growth (for the 15 minutes that the hoof is immersed).
Are either of these even close? These same people also bring out chiropractors twice a month or so to “adjust” the horses’ backs.