International Omega-3 Learning and Education Consortium for Health and Medicine

More than ever before, pet owners are more conscious of their pet's nutrition and health status. A burgeoning area of interest to enhance pets' health is supplementing their diets with omega-3 fatty acids, especially preformed long chain omega-3 fatty acids, such as eicosapentaenoic acid (EPA, 20 carbon fatty acid) and docosahexaenoic acid (DHA, 22 carbon fatty acid). A 2007 survey of 1000 pet owners revealed that more than 80% of respondents believe that omega-3 fatty acids are one of the most essential nutrients to have in the food they and their pets eat. Here we present some basic information on essential fatty acids and, in particular, the omega-3 fatty acids.

Two families of fatty acids are essential to companion animals: the omega-6 and omega-3 fatty acids. These two families of fatty acids are both polyunsaturated fatty acids (PUFA) but they differ at the location of their double bonds along the carbon chain. Although these PUFA are structurally similar, their metabolites have distinctly different biological and physiological effects.

The first family of essential fatty acids is called omega-6 fatty acids and generally refers to linoleic acid since this is the basic compound that can be further elongated and desaturated to longer chain derivatives, predominately arachidonic acid (AA), that serve as precursors of a wide array of biologically active compounds, such as prostaglandins, leukotrienes, and thromboxanes. Both dogs and cats need linoleic acid for normal health. AA is essential to cats since they lack adequate delta-6 desaturase activity, a rate-limiting enzyme during the conversion of LA to AA ¹.

The second family of essential fatty acid is called omega-3 fatty acids and generally refers to alpha-linolenic acid (ALA, 18 carbon fatty acid). As with the omega-6 fatty acids, cats do not have an adequate ability to form their own longer chain omega-3 fatty acids from ALA so they need to consume preformed long chain omega-3 fatty acids, such as EPA and DHA, in order to obtain any benefit from these fatty acids. Since the structures of the two families of fatty acids are very similar (ALA the omega-3 family and linoleic acid the omega-6), they compete for the same enzymes that convert them into their respective biologically active metabolites (EPA and DHA from the omega-3 fatty acid ALA and AA from the omega-6 fatty acid linoleic). Both families of fatty acids serve as cellular signals that are important in a variety of biological processes including immune function, blood clotting and inflammation. Generally, the compounds derived from the omega-6 fatty acids are usually more potent than those derived from omega-3 fatty acids.

Although omega-3 fatty acids are not traditionally recognized as essential for dogs and cats, strong evidence has emerged from past and ongoing research that suggests pets, similar to humans, can benefit greatly by incorporating omega-3 fatty acids into the diet. With the right type and amount of omega-3 fatty acids in the diet, the potential contribution of omega-3 fatty acids to the health of our dogs and cats is very promising. Appropriate amounts of omega-3 fatty acids in the diet benefit neural development, the cardiovascular and immune systems, skin and fur health, and pregnancy and lactation.

When purchasing pet foods, the pet owner should carefully examine the nutrient label and make certain that the omega-3 fatty acid species are clearly stated with creditable ingredient sources, such as fish, fish meal and fish oil, which are rich in DHA. Dietary DHA is critical for optimal neural development in young cats and dogs because DHA synthesis in their bodies is limited. Pet food products claim to have omega-3 fatty acids but many primarily contain ALA (from vegetable oils) and may not provide as much of a benefit since this omega-3 fatty acid is poorly converted to DHA in the body. Checking manufacturers' websites is a good way to find out what is in the pet food and specifics of the ingredients (please see Pet food products).

To recommend omega-3 fortified pet foods or supplements to pet owners, one should be careful in determining the appropriate dosages for different health issues and at specific developmental stages. Improper use of supplements containing omega-3 fatty acids could lead to potential health problems, such as blood clotting problems and relative deficiencies of Vitamin E and other vitamins. It is important to recognize that a supplement that contains a large amount of omega-3 fatty acids in a concentrated form often comes with a high amount of vitamins A, D, and E. One should be very careful in weighing the benefits and potential adverse effects of different supplements. For more information, please go to our website and read the section on "Veterinarians | Diet & Health". Our website offers a Library with comments and key points for published articles on companion animal nutrition and health. A search link for NIH PubMed Central (omega-3 search on NIH digital archive) is also present on the publication main page for your convenience.

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