This past summer I was treating my mare's respiratory allergies with antihistamine. In addition, we stripped her stall of shavings, soaked her hay and seemed to have things under control. With our rainy winters there are lots of allergens in the environment. That coupled with the re-introduction of shavings to her stall, the nasal discharge resumed. I was sceptical about using Spirulina. However in discussion with my vet who endorsed its use and from my previous experience with other Mad Barn products , I thought it was worth trying. My mare has been on Spirulina for approximately three weeks and there is no sign of nasal discharge or respiratory problems. Although normally a chow hound, we had to gradually introduce the product over a period of a few days. She is now on the full rec...