What you refer to as hoof rot I think is the same thing that I refer to as foot rot. I usually don't notice foot rot in the cattle until they start favoring one of their legs - because it is so painful it is noticeable very quickly in the early stages before the cow goes down. For a commericial medication I use Liquidmycin LA - 10-15 cc depending on size - works very fast - animal back to walking normal in 12-24 hours. A couple of the old fashion remedies I am aware of which was used 50 plus years ago is a footbath consisting of a 5%bluestone solution - you can use a kids wading pool and have the animal walk through this footbath twice a day. Bluestone is very toxic and poison so be sure to cover the pool when not in use so your other animals do not drink it. The other method is spraying the animals feet (Hooves, claws etc) with a mixture of creolin and water on a daily basis - this is very stinky stuff. Before you try any of these talk to Pooperscooper as she is the horse expert - these remedies I know are effective on cows but not sure about horses.