Been using Clarity for many years. My old boy has equine asthma-that is untreatable with prescription drugs now, and he gets a terrible hacking cough. I tried various natural remedies, none of which really worked. I decided to try Clarity, as i've been a customer of Feedmark for many, many years. Blimey, what a difference after a few days of using it. He is a very fussy eater, so i introduced it really slowly. It isnt the cheapest, but, i wouldnt feed anything else-like i said, he's been having it added to his evening feed for the last few years-and it really does help