Omega-3s Helpful for Horses with Metabolic Syndrome

Obesity affects one-quarter to one-half of the horses in the world. With obesity often comes insulin dysregulation, both of which are defining characteristics of equine metabolic syndrome (EMS). Another facet of metabolic syndrome is body-wide tissue inflammation, contributing to increased risk of laminitis. In an effort to pinpoint a nutritional strategy to reduce inflammation in this target population, researchers at the University of Kentucky supplemented EMS-affected horses with microalgae rich in docosahexaenoic acid (DHA), an omega-3 fatty acid.^*

“The researchers approached this study with a measure of precedence, as DHA and eicosapentaenoic acid (EPA), another omega-3 fatty acid, have been shown to improve glucose clearance, reduce inflammatory mediators, and boost circulating levels of fatty acids in horses without endocrinopathy. The effects of omega-3 fatty acids on EMS horses specifically, however, have never been quantified,” said Catherine Whitehouse, M.S., a Kentucky Equine Research nutrition advisor.

Researchers chose 10 mixed-breed, mixed-sex horses of varying ages for the study. All horses met the diagnosis criteria set forth by the ACVIM consensus statement on EMS, which was published in 2010.

During the study, horses were either fed 16 g of DHA each day as a DHA-rich microalgae or served as controls for 46 days. Inflammatory status, circulating fatty acids, triglycerides, leptin, and adiponectin concentrations were measured. A protein hormone, adiponectin helps regulate glucose levels and fatty acid breakdown. Insulin and glucose dynamics were evaluated with oral sugar testing and intravenous glucose tolerance testing.

Following the experimental period, supplemented horses had increased levels of several circulating fatty acids, notably DHA. Horses on the DHA-supplemented diet also had lower serum triglyceride levels following the trial. Though this was a preliminary study, results indicate that DHA-rich microalgae “alters circulating fatty acids, modulates metabolic parameters, and may reduce inflammation in horses with EMS.”

“Though this work is preliminary, it lays the groundwork for further studies that will help gauge the effectiveness of DHA in controlling the inflammatory aspects of EMS. When combined with an appropriate diet and exercise, supplementation with DHA-rich products is a logical management approach,” said Whitehouse.

Without question, one of the best sources of DHA for horses is EO-3, a marine-derived product suitable for all classes of horses. Fish oils, like EO-3, are direct sources of DHA and EPA, which are the most useful omega-3 fatty acids in terms of conferring health benefits to horses.

Aside from diet management, exercise and weight loss will often help horses with insulin dysregulation.

^*Elzinga, S.E., A. Betancourt, J.C. Stewart, M.H. Altman, V.D. Barker, M. Muholland, S. Bailey, K.M. Brennan, and A.A. Adams. 2019. Journal of Equine Veterinary Science 83:102811.