Know Your Omegas

Understanding omega fatty acids in the equine diet

Research into every aspect of the equine diet underpins ongoing product development at Top Form Nutrition, facilitating the highest standard of nutritional support for breeding, training and performance. This factsheet sets out an overview of current knowledge relating to the addition of Omega 3 and 6 Fatty Acids to the equine diet.

Lipids, (fats and fatty acids), make up the majority of cell membranes and are vital for many different functions in a healthy horse. Amongst the different types, some can be synthesised by the horse, but some cannot and these must be included in the diet, hence the term ‘essential fatty acids’ (EFAs).

Amongst the EFAs are the omega-3 and omega-6 fatty acids and whilst there is much discussion about what the ideal ratio of omega-3 to omega-6 fatty acids for horses might be, researchers have not yet been able to define this. One isn’t ‘better’ than the other, it’s simply that the two types have different roles in the body and must be present to maintain optimal health.

Omega-3s are known to balance immune function, support gastrointestinal efficiency and reduce inflammatory responses, hence they are protective of joints and ligaments, reduce airway inflammation, reduce allergic skin conditions and decrease nervous behaviours. The essential omega-3 that must be in the horse’s diet is Alpha Linolenic Acid (ALA), from which the horse can manufacture two other omega-3s; docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).

Omega-6s play an important role in vision, blood clotting, the production of steroids and hormones, and regulating cell division. The most common omega-6 added to the equine diet is linoleic acid (LA), which can be converted in the body to arachidonic acid or the prostaglandin series PG1. Arachidonic acid can be further converted to the prostaglandin series PG2. These mediate or modulate inflammatory reactions.

Continuing research is revealing more information about the benefits of supplementing the horse’s diet with these EFAs. As herbivores, horses are naturally adapted to a diet rich in omega-3s compared to omega-6s and there is only one naturally occurring source of omega-3s in the equine diet - fresh grass or forage. Fresh grass contains four times more omega-3s than omega-6s.  (although hay has virtually none) whereas the grains and seeds in many equine feeds tend to be higher in omega-6s.

Hence it can be seen that supplementing a high quality source of omega-3s is likely to provide numerous benefits to the horse. Unrefined linseed oil, derived from flax seeds, is very high (53%) in ALA and close to the natural ratio (4:1) of omega-3s to omega-6s present in fresh grass.

It should be noted that whilst fish oil is commonly understood to be a good source of omega-3s, as horses are herbivores, it is generally recommended that they are fed only those oils derived from plant sources. In addition, whilst fish oils are high in DHA and EPA, they do not provide the essential omega-3 ALA. Therefore supplementing the diet with linseed oil will better mimic the omega-3s found in plants, which horses have evolved to eat.

Other oils sometimes fed to horses, including corn oil, sunflower oil and soya oil are high in omega-6s and will not deliver the benefits of linseed oil.