Fish Oils and Omega-3s: Source MattersBy Kentucky Equine Research Staff · February 6, 2017
The benefits of omega-3 supplementation are becoming increasingly clear, thus skyrocketing the popularity of products containing long-chain fatty acids. Is there a difference between omega-3 sources, or are all omega-3s created equally? The short answers are yes and no.
Omega-3 fatty acids are essential in the diet, meaning the body cannot make its own. There are three main forms of omega-3s: alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). The body converts ALA into EPA and DHA, but this process is inefficient in mammals*. For this reason, finding a good source of dietary EPA and DHA is helpful for increasing omega-3 fatty acids in the body.
Omega-3 fatty acids have anti-inflammatory properties, and may help manage conditions such as airway inflammation, arthritis, and poor semen quality in stallions. “We have also found omega-3 fatty acids to be very helpful in treating skin conditions,” adds Kathleen Crandell, Ph.D., a nutritionist at Kentucky Equine Research (KER). Ingestion of EPA and DHA can partially replace omega-6 fatty acids in cell membranes, lessening the inflammatory response**.
Keep in mind, it is important to balance omega-3 fatty acid intake with that of omega-6, as the two work together for proper immune function and cell membrane structure. The ideal balance is not known in horses, but in humans, recent recommendations suggest an intake ratio of 5:1 to 10:1 of omega-6:omega-3**.
Omega-3s have different sources. ALA is commonly found in vegetable oils, flaxseed, flaxseed oils, chia seeds, leafy green vegetables, pasture, and hay. EPA and DHA are found in fish, algae, and seaweed.
Fish oil. Cold-water fish are rich sources of EPA and DHA. With the environment and palatability in mind, KER developed EO•3 using menhaden oil, from menhaden fish, a plentiful, sustainable, low-mercury source. The smell of fish oil can be off-putting to horses, so KER has meticulously deodorized EO•3 and has added flavoring that is readily accepted by horses.
Cod liver oil. Another source of omega-3 fatty acids is cod liver oil, which, as the name suggests, is derived from the livers of codfish. Cod liver oil may contain slightly less EPA and DHA compared to fish oils, which are usually derived from flesh. Unlike fish oils, cod liver oil also contains high concentrations of vitamins A and D*. Excessive vitamin A is known to cause birth defects and should be avoided in diets fed to pregnant mares.
Plant sources. While sources such as flaxseed and chia are rich in ALA, the body’s ability to convert ALA to EPA and DHA can be limited. Vegetable oil is a popular addition to equine diets, especially for horses in need of extra calories. However, some vegetable oils contain high levels of omega-6 fatty acids and practically no omega-3s, potentially disrupting dietary balance of omega-6 to omega-3 intake.
In EO•3, 25% of the fat content is EPA and DHA, whereas about 3% is omega-6. Thus, EO•3 is an excellent option for increasing EPA and DHA intake, especially for horses consuming high-grain diets or for those who suffer from inflammatory conditions. When considering an omega-3 fatty acid supplement, it is important to evaluate the content of EPA and DHA. EPA and DHA are important for managing inflammation and immune support, and helping to maintain a dietary balance of omega-3 and omega-6 fatty acids.
*Warren, L.K. and Vineyard, K.R. 2013. Fat and fatty acids. In: Equine Applied and Clinical Nutrition. pp 136 – 155. Geor, R.J., Harris, P.A. and Coenen, M., Eds. Saunders Elsevier. New York, NY.
**Nutrient Requirements of Horses, 6th Edition. 2005. Fats and fatty acids. National Academies Press, Washington, D.C. pp. 44-53.