I don't know if it is the best way but works and is cheap, take flat head wire dikes and cut off several small warts with the dikes, crush them up, and feed them to the animal, rest of warts will drop off shortly after a few days. Works like an innoculation, I still do this with my cattle, when we have warts, best way to prevent is new needle with every animal, sterilize dehorning and tatoo equipment between each animal, use Nolvasan, Surgical scrub, bleach, whatever you use to clean your surgical tools, or tools that are used in contact with blood, and go from animal to animal.
