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What are antioxidants and how do they help my horse?

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Oxidation is a normal metabolic process that allows horses to transform the carbohydrates, fats, and proteins they devour in meals to energy. The creation of free radicals – compounds that have the potential to irreparably damage cells – is one unfortunate and unavoidable spinoff.┬áIf left unchecked, the oxidation that occurs at the cellular level in horses and other mammals can cause muscular fatigue severe enough to compromise performance. When a horse is exercising strenuously, natural stores of antioxidants have difficulty providing sufficient protection against the cascade of free radicals generated from aerobic metabolism, making it necessary to supplement antioxidants.

Vitamin E contributes most generously to the natural antioxidant defenses of the horse. Cereal grains typically fed to horses have variable vitamin E concentrations. Horses may derive sufficient amounts of vitamin E from fresh forage or hay; however, the vitamin content abates as forages mature and are harvested and stored.

Because of the irregularity in vitamin E content of forages and other feedstuffs, the nutrient is often added to fortified feeds. While synthetic forms of vitamin E have long been the standard source of added vitamin E in feeds and supplements, research has shown that natural-source vitamin E, depending on the preparation, is 1.6 to over 6 times as bioavailable as synthetic vitamin E. Vitamin E is often linked with selenium, a micromineral that possesses potent antioxidant properties.

Vitamin C, often referred to as ascorbic acid, also plays a pivotal role in neutralizing harmful free radicals. Because of its water-soluble nature, vitamin C can work both inside and outside the cell to combat free radical damage. Vitamin C also helps by regenerating vitamin E. The horse does not have a requirement for supplemental vitamin C, because it normally can be formed in the liver from glucose.