Volcanically derived natural mineral clays containing aluminosilicate the zeolites of significance in equine nutrition are the clinoptilolites which have a range of medically and nutritionally interesting properties. Principally they can provide a bio-available source of Silicon which was demonstrated to have a positive benefit when fed to young racehorses in that they were able to train and race for longer with fewer bone and collagenous tissue related breakdowns. The effect was attributed to improved bone density and raised production of glycosaminoglycans in joint cartilage which has been shown in chickens, but without that hypothesis being proven in horses.
The other property of zeolites is their capacity to absorb a range of ions, elements and chemicals including toxins into their unique charged lattice structure. They have the ability, due to housing charged ions inside their microscopic structure, to attract and hold ammonium ions removing them from the substrate, as well as some mycotoxins like Aflatoxin, trace element and heavy metal ions. These properties have been exploited in livestock to improve gut health by reducing toxin load, boost feed conversion efficiency, and positively benefit immune system function.
Whilst most research on zeolites has been done in humans and other livestock the positive results and broad range of potential beneficial effects make this class of clays a promising feed supplement for horses.