Oh thank god! I was going to make a thread asking this too.... I took rena to my friends aunts boarding barn for the weekend to trail ride with my friend, and the bugs are so bad trail riding was no fun! the horses had so much fly spray on they were STICKY, so it sucked.
But when i got home I asked my mom if we could just use off on rena, because we used off and the bugs never touched us. she said she used it on her hroses, they were all fine, and she even asked the vet one time, and he said its fine!
I was also thinking, if your worried about how harsh it is and stuff, use 'kids off' If we use it on toddlers, im pretty sure a hrose can handle it! lol, as long as they arent allergic.
If there are no horses in heaven... im not going.