Could you use a vinegar to treat a mild skin fungus on a horse?

I was reading about skin fungi since my horse as a mild case of dry skin and some fungus on her chest. I was off to grab the betadine but I was just wondering if perhaps a vinegar or apple cider vinegar could also help break down a fungus? Has anyone tried this before? I know vinegar would not hurt a horse regarding skin as I put vinegar in my fly spray (it makes them sweat vinegar keeping flies away longer) so I was just curious.