Use the apple cider vin. As a preventative. During really wet months I try to keep the girls feed cleaned out and then spray some ACV on them. Put it in a spray bottle it makes the task much easier.
I also took the recommendation of my farrier and barefoot trim advocate Pete Ramey. Mix equal parts of athletes foot cream containing clotrimazole and triple antibiotic ointment like Neosporin.
I keep large syringes and put the paste into one of them. That way you can really get it down in the crevices.
Its well the money to keep an assortment of syringes around for this sort of thing. I get them via Dr.s Foster and Smith