. Vitamin E is unique among vitamins. As alpha-tocopherol, vitamin E is notably essential for the proper function of the reproductive, muscular, nervous, circulatory and the immune systems. Its antioxidant property is its prime function. Vitamin E, which can't be synthesized in your pet's body, is possibly the most important and essential antioxidant for protecting cell membranes from free-radical damage. Vitamin E works in concert with other antioxidants, protecting and reinforcing the effect of vitamin C and beta-carotene, and working together with selenium. Vitamin E may also work synergistically with taurine.
Seed oils such as soy and sunflower seed and organ meats such as liver and spleen are higher in vitamin E. In the wild, cats and dogs may naturally obtain vitamin E from organ meats. Today's pet foods are supplemented with vitamin E. Most critical for pet diets is the increase in vitamin E requirement with an increase in dietary poly-unsaturated fats. Fish oils in cat foods and other fat sources of unsaturated fats, requires an increased need for vitamin E.
Synthetic vitamins are, for the most part, equal in efficacy to natural source vitamins. Not so for vitamin E. The best vitamin E is isolated from seed oils, as opposed to synthetic vitamin E made from petrochemicals. The body preferentially transports and incorporates natural-source vitamin E. Synthetic vitamin E is not as biologically potent in comparison. The difference between the two is the difference in the chemical structure of the two, just like apples and oranges.
For your pet, natural vitamin E is better than synthetic. It functions better to provide their enhanced antioxidant need. From mice to elephants it has been shown that natural vitamin E has more punch, more 'bounce per ounce' than synthetic. There are physiological differences in its absorption, transport, utilization and tissue retention. Though past research has shown that natural vitamin E is 36 percent better than synthetic, current research in several species, including humans, shows a 200 to 300 percent potency of natural versus synthetic vitamin E.
For dogs and cats, vitamin E is essential for health. Healthy muscles, retinal (eye) health and reproductive success all are linked to sufficient vitamin E. Vitamin E is especially necessary to newborn kittens and puppies
; since placental transfer is poor, first milk, colostrum, is important to provide adequate vitamin E. A sufficient amount of vitamin E is important to prevent oxidation of body fats. As polyunsaturated fats (PUFAs) are increased in dog and cats diets, the requirement for vitamin E increases. Years ago, without this knowledge, diets high in PUFAs (fish, fish meal, fish oils), and not supplemented with sufficient vitamin E, led to 'yellow-fat' disease – rancidity and destruction of body fat, leading to death in puppies and kittens.
According to the National Research Council (NRC), the need for vitamin E in the diet of cats is markedly influenced by dietary composition. Though 30 IU per kilogram of diet is considered the minimum requirement for cats, 50 IU per kilogram of diet is probably better, considering the high PUFA-containing diets many pet cats eat. Actually a high PUFA diet of tuna or other fish probably requires three to four times the minimum.
Similar to cats, the dietary requirement of dogs for vitamin E is closely associated to the dietary concentration of PUFAs. It has been reported that a smaller amount of vitamin E would not sustain reproduction in fox terriers fed unsweetened, irradiated evaporated milk, while a slightly larger amount would. However, one pup in four from a bitch receiving the higher level of vitamin E showed slight muscular dystrophy. In beagle puppies, 30 IU vitamin E per kilogram of diet prevented deficiency both clinically and histopathologically. According to the NRC, the recommended allowance for maintenance, reproduction and growth of dogs, should be satisfied by 20 IU vitamin E/kg diet, a little more for pregnancy and a little more for growth.Pet Foods Needs Antioxidants, Too
Today's pet foods are supplemented with other antioxidants for the stability of the food. Dry pet foods are especially susceptible to fat rancidity and deterioration. Since dry dog and cat foods need to be stable, with sufficient shelf-life, antioxidants are included to keep them from spoiling. Today in premium pet foods, 'natural' antioxidants including mixed tocopherols, and rosemary extract, along with vitamin C and citric acid are often blended to stabilize fat sources, instead of chemically synthesized antioxidants such as BHA, BHT, and/or ethoxyquin.
Mixed tocopherols are different from vitamin E supplementation for your pet's health. Mixed tocopherols are composed of alpha, beta, delta, and gamma tocopherol, while vitamin E activity for your pet's health and nutrition is solely alpha-tocopherol. Although your pet foods may be stabilized with mixed tocopherols, vitamin E is usually provided by synthetic vitamin E.Look For Natural Vitamin E in Your Pet's Food
For your own personal vitamin E needs, you search out natural-source vitamin E, d-alpha-tocopheryl acetate, that says "natural vitamin E" right on the bottle. You prefer natural vitamin E. Expect no less for your pet. Therefore, look for natural vitamin E in your pet's food. Look for d-alpha-tocopheryl acetate, natural vitamin E in the ingredient list of his dry dog or cat food. Similarly, when you look for shelf-life protection in your pet's food, look for mixed tocopherols, not BHA or ethyoxyquin.
Dietary antioxidants are important for your pets. Make sure your pet's food contains the necessary antioxidants, so that Fido will be able to run free, not the free-radicals.