At the Purina Equine Veterinary Conference, held Oct. 17-19 in St. Louis, Mo., Karen Davison, PhD, manager of Equine Technical Services for the Horse Business Group of Purina Mills discussed managing inflammation and oxidative stress in horses through their diets A horse that stands idle, breathing, eating, and digesting food, is affected by tissue changes caused by normal metabolism of simply being alive; exercise amplifies oxidative tissue changes. Oxidative stress is caused by the toxic byproducts (free radicals and peroxides) of metabolism, and occurs to some degree in every tissue.

Davison reminded the audience that inflammation is valuable in that it spurs normal immune and healing responses in the horse. At times certain inflammatory mediators “switch teams” to serve beneficial functions. Therefore, research studies that measure a single biological marker of inflammation might not truly reflect treatment effects on the inflammatory process. An owner should be aware of comprehensive data related to a supplement while also being wary of anecdotal recommendations.

She noted that in many cases product marketing often precedes research. This means that information about the effectiveness of nutritional supplements provided to horse owners might not be accurate.

A nutritional product reported to combat inflammation and oxidative stress is one of the group omega fatty acids: omega-3s are touted as having anti-inflammatory properties while omega-6s have been suggested to induce inflammation. Davison noted omega-6 fatty acids are important for skin, hair, and general health. Both omega-3 and omega-6 fatty acids use the same enzymes for their metabolism, so an imbalance of one over the other could create inflammation, immune deficiencies, or bleeding problems. The ideal ratio of omega-3s and omega-6s has not yet been defined in the horse, and she noted that extrapolation from digestive physiology of other species might be in