coat condition. The National Research Council (NRC) recommends a 2.6:1 to 26:1 omega 6:3 ratio for adult dog maintenance diets. The proper ratio of these fatty acids is crucial because each has an opposing role in inflammation within the body and both compete for the same enzymatic pathway. Dogs, like many mammals, lack the desaturase enzymes capable of interconverting omega 3 and 6 fatty acids. Therefore, the amount of inflammation in the body is dependent on the ratio between omega 3 and 6 fatty acids. Too little inflammation suppresses the immune system and the body's ability to heal, however excessive inflammation can irritate the skin and reduce the coat's overall appearance. Aside from omega fatty acids, lipid content in the canine diet is an important aspect of coat health. The fat soluble vitamins (A, D, E and K) require lipids present in the diet for absorption, transport and deposition in canine adipose tissue. The specific role of vitamins A and E for coat health are explored elsewhere in this article, as they pertain to immune function. Another pet food regulating body, the Association of American Feed Control Officials (AAFCO), recommends that Vitamin E supplementation increase as polyunsaturated fatty acids are added to diet in order to counteract lipid oxidation and maintain the potency. In addition, high fat diets in dogs were shown to dramatically improve coat sheen and appearance. It is thought excess cholesterol esters are incorporated into the hair follicle, leading to the improved coat appearance. The same study, by Kirby, Hester and Bauer (2007), stated the optimal approach to an improved coat in dogs is a combination of increased dietary fat and the proper amount of polyunsaturated fatty acids. Omega 3 (linolenic acid) Omega 3 fatty acid, also known as linolenic acid, is an anti-inflammatory compound. Linolenic acid is found in the oil from flaxseeds, soybean and canola. Some better known examples of linolenic acid are the metabolic derivatives eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA). EPA inhibits the enzyme delta-5-desaturase, which prevents the synthesis of arachidonic acid which is an inflammatory omega 6. DHA acts even earlier in omega 6 metabolism, by inhibiting delta-6-desaturase. The anti-inflammatory properties of omega 3s stem from their ability to inhibit the inflammatory action of omega 6 fatty acids. A functional minimum has not been set forth by AAFCO, as one has yet to be determined. A reduction in inflammation of somatic