Omega-3 and -6 Fatty Acids for Horses: Is There an Ideal Ratio?

The “omega movement” has been gaining momentum for over a decade, and knowledge regarding health benefits of omega fatty acids for horses has grown in leaps and bounds. Omega-3 fatty acids are now included in a vast array of equine nutritional supplements, including those designed for coat, joint, and hoof health. Omega fatty acids are used for:

• Improving reproductive success;
• Helping horses with allergy and immune conditions;
• Exercise recovery, tying-up, and other muscle problems;
• Endocrine issues;
• Respiratory diseases such as heaves; and
• Neurological conditions.

Omega fatty acids are a type of polyunsaturated fatty acid (PUFA), meaning simply they have more than one double bond between adjacent carbon atoms (instead of only a single bond like in “saturated” fats such as butter). Corn, safflower, and sunflower oils are rich in linoleic acid, which is a PUFA. That said, flaxseed (linseed) and chia both contain alpha-linolenic acid, which is also a PUFA.

The difference? Linoleic acid is an omega-6 fatty acid that is metabolized in the body to produce arachadonic acid. In turn, arachadonic acid is metabolized to prostaglandin E2 and other potent mediators of pain and inflammation. In contrast, alpha-linolenic acid is converted to eicosapentanoic acid (EPA), a type of PUFA found in cold-water fish. Dietary EPA, EPA produced from the metabolism of alpha-linolenic acid, as well as dietary DHA (another PUFA in fish oil) compete with arachadonic acid and suppress inflammation.

It is important to remember that omega-6s aren’t all bad and do play important roles in the body because inflammation is a necessary response for healing. However, there is a delicate balance between the omega-3 and omega-6 fatty acids.

“Too many omega-6s and not enough omega-3s can result in excessive inflammation in the body. Therefore, having adequate amounts of omega-3s in the diet to moderate the pro-inflammatory response of the omega-6s is desirable,” explained Kathleen Crandell Ph.D., an equine nutritionist at Kentucky Equine Research (KER).

As described in Nutrient Requirements of Horses, published by the National Research Council, nutritional supplementation with fish oil, flaxseed oil, and flaxseed increases EPA levels in the horse’s body while decreasing arachadonic acid levels.

“Unfortunately, ideal omega-3 to omega-6 ratios for all species are not established. While we continue to conduct research in this field, one way to increase omega-3 fatty acids is to replace corn, safflower, and sunflower oils with oils higher in omega-3 fatty acids, like canola, flax, fish oil, or supplement with flax or chia seed. EO-3, a marine-derived product developed by KER, is a palatable oil that is top-dressed onto the feed and containing both EPA and DHA,” Crandell shared.

*Ross-Jones, T.N., C.W. McIlwraith, J.D. Kisiday, T.M. Hess, D.K. Hansen, and J. Black. 2016. Influence of a n-3 long-chain polyunsaturated fatty acid-enriched diet on experimentally induced synovitis in horses. Journal of Animal Physiology and Animal Nutrition 100(3):565-577.