Comparing the Effects of Two Equine Omega-3 Fatty Acid Supplements

Omega-3 fatty acids have proven to be beneficial for horses with arthritis or other inflammatory conditions, but when it comes to choosing a supplement, which one is best? There are two sources of equine omega-3 fatty acid supplements--one derived from algae and fish oil and the other derived from plants. Recent research performed at Colorado State University (CSU) shows that although the equine body incorporates the two supplements differently, each has its benefits.

"(This) study, to the knowledge of the authors, is the first trial to evaluate the effects of supplemental dietary n-3 (omega) fatty acids on skeletal muscle fatty acid composition of horses," reported Tanja Hess, DVM, DSc, PhD, assistant professor of equine sciences at CSU, in the study.

Along with evaluating effects on skeletal muscle, Hess and colleagues also aimed to investigate how both a marine- and a plant-based omega-3 fatty acid supplement would affect plasma and red blood cells (RBC) in the horse.

The researchers acclimated three groups of seven horses to identical diets of alfalfa/bromegrass hay and rolled barley. The first group (marine) consumed 38 grams of a commercial algae and fish oil pellet, containing the following specific n-3 fatty acid amounts:

  • 2 g Alpha-linolenic acid (ALA, essential omega-3 fatty acid, "essential" meaning it must be obtained through the diet and cannot be synthesized by the body.);
  • 7.6 g Eicopentaenoic acid (EPA);
  • 26.6 g Docosahexaenoic acid (DHA);
  • 1.6 g Docospentaenoic acid (DPA).

The second group (plant) consumed 38 grams of a commercial ground flaxseed product containing only ALA. The third group acted as a control, receiving no supplemental n-3 fatty acids except for the ALA present naturally in the barley and hay.

For analysis purposes, researchers acquired blood samples and gluteal (rump) muscle biopsies (to determine if dietary supplementation of fatty acids has an impact on skeletal muscle fatty acid composition) on Days 0, 30, 60, and 90 during the four-month study.

Key study results include:

  • EPA and DHA in plasma and RBC were only identified in marine horses;
  • EPA and DHA were found in muscle tissues of all three groups (although the highest levels were found in marine group horses), indicating conversion, though limited, from the "parent fatty acid," ALA; and
  • Flax horses had increased muscle DPA ("which also has some inflammation mediating functions," said Hess), again indicating conversion from ALA.

"As far as the authors are aware, this is the first study to demonstrate that dietary fatty acid supplementation will affect muscle fatty acid composition in horses," the team relayed in the study. "Incorporation of n-3 long chain, highly unsaturated fatty acids into blood and muscle depends directly on dietary supply of specific fatty acids."

Hess relayed that further studies are needed in order to evaluate the effects of n-3 long chain, highly unsaturated fatty acid on inflammation, inflammatory conditions, and inflammatory insulin sensitivity.

The study, "Effects of two different dietary sources of long chain omega-3 highly unsaturated fatty acids on incorporation into the plasma, red blood cells, and skeletal muscle in horses," appeared in the Journal of Animal Science. The abstract is available online.

Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.