My last horse responded to it well. I syringed it directly into his mouth (he was fine with that) to make sure he got all of it, because results were mixed when I put it on his feed on whether he'd eat it or not. You can mix it in the feed.
I felt like it helped my horse when he had some irritation from his allergies, which were primary dust induced.
I mixed it into our old horses feed on the reccomendation of his vet. It smells really strong and I wasn't expecting him to eat it but he didn't mind at all. It certainly seemed to help at first. I think for milder respiratory issues its really good.