There is much debate surrounding the use of supplements in equine diets, but adding fish oil to a horse's feed to increase omega-3 fatty acid intake can have a positive effect on exercising horses' health and endurance, according to Kyle Newman, PhD, of Venture Laboratories. Newman presented a study on the subject at the Veterinary Sport Horse Symposium for horse owners, held Sept. 22-24, 2010, in Lexington, Ky.

According to Newman, omega-3 fatty acids' effects on equine health include "increased vascular compliance, anti-hypertensive properties (lower blood pressure), inhibited production of cytokines (immunoregulatory proteins) involved in chronic inflammatory and autoimmune diseases, positive effects on fetal development, and improved semen quality."

During his presentation, Newman focused specifically on how the fatty acid fish oil might benefit sport horses. He cited a study conducted by C.I. O'Connor et al. in 2004 that involved 10 mature geldings on an eight-week exercise program. Four horses were supplemented with corn oil and six were supplemented with fish oil at 180 g/day (which delivered approximately 30g /day of omega-3 fatty acids). Researchers then measured and compared the heart rates, packed cell volume (the amount of red blood cells in the bloodstream), insulin concentrations, plasma glucose, and serum cholesterol concentrations of the two groups of horses