Put the Vaseline in the container and melt it over boiling water, mix in the tea tree oil and let it harden. Tea Tree Oil can be purchased in health food stores as well as other places. I carry a container in my saddlebag at all times. This is what I use for my fussy horses. Just before you are ready to medicate your horse, add the Bute which has been well crushed.
Most pharmacies sell a cheap, plastic pill crusher.
Put the mixture in a dose syringe and squirt it in the back of the horse's mouth. Ashley J adds that she cleans her worming tubes to administer her bute applesauce mixture. It doesn't wipe off, my husband offered me his waterless cleaner, GOOP, and it took that junk off the unwanted areas. I have also used it to remove pine tar from hair and other sticky stuff. The GOOP then will wash off with water taking the junk with it.