few years back we had a few heifers that had ring worms, I asked and asked vets, feedstore personel, etc what to treat em with....got answers like 50/50 bleach water treatments for 7 consecutive days or iodine scrub for the same length of time, givin a cow a bath in the stuff for 7 days in a row is alot of aggrivation, I asked the pharmacist at my local drug store about ring worm, he told me..well it's a fungus in the same family with athletes foot. so the spray ya buy will take care of it. so I went to the shelf, and bought the "store brand" about 6 cans, I wanted to make sure I had enuff to go around to any and all heifers that had it. Ran them thru the chute and sprayed each spot I found, only used one can and part of another and treated one time. Ring worms gone and new hair grew back in less than a week. Woo hooo...can of spray only cost 1.97 cheapest fix for cows that I've come across so far.
Although I did get a really strange look from the woman at the register....but oh well..hehe