Can Vitamin C Improve Horse Nutrition?
Vitamin C (Ascorbic Acid) is used across different species and in different physiological states. Animals such as guinea pigs and primates cannot synthesize ascorbic acid and therefore have a requirement. The requirement for ascorbic acid in primates and guinea pigs is met through supplementation. Other species such as swine, aquaculture, equine, bovine and ovine have been shown to respond to supplementation of ascorbic acid especially under high stress situations. For example, Chirase and coworkers at Texas A & M showed in 2005 that in calves where blood vitamin C (ascorbic acid) was measured before and after shipment from Arkansas to Texas, calves’ average blood vitamin C concentrations decreased from TN values of 2.67 micro Moles/liter (uM/L) to 0.16 uM/L (TX), with some calves below detectable levels. This result was very surprising because cattle can synthesize vitamin C. Chirase and coworkers recommended that marketing and transit stress were either too intense resulting in the depletion of the supply of ascorbic acid in calves or the rumen was not well developed to support vitamin C synthesis. Consequently, calves of this size (dairy and beef) should be supplemented with ruminally protected vitamin C to meet their daily requirements and/or to counter physical, biological and chemical stressors in the production system.
Horses have not been traditionally fed supplemented ascorbic acid because of their ability to synthesize ascorbic acid. Similar to many species however, in situations of high stress such as performance and where immune health is impacted supplemental ascorbic acid may be required. Taking into consideration situations of high performance ascorbic acid plays a role in collagen formation. In collagen formation, ascorbic acid is required for the formation of two essential amino acids. Without the presence of ascorbic acid the strength and integrity of collagen is impacted. We must remember that collagen is involved in bone structure, maintaining blood pressure and in wound healing.
Research has shown that under stressful situations the demand for ascorbic acid increases and there is a decrease in blood ascorbic acid. Such a decrease in blood ascorbic acid is correlated to overall decreases in the antioxidant capacity. Oxidative stress has been shown to be a contributing factor to the incidence of joint disease and cell membrane damage in horses. Supplementing ascorbic acid to horses have been shown to reduce exercise induced oxidative stress. Likewise, adding 10 grams per day of ascorbic acid have been shown to help maintain serum alpha tocopherol levels.
The case for coated microencapsulated stabilized ascorbic acid
Ascorbic Acid (Vitamin C) is a nutrient that readily undergoes chemical changes especially when exposed to air. It oxidizes readily. When exposed to light, air, heat and moisture it rapidly loses its potency. Prolonged storage of feeds with raw vitamin C that is in feeds or added to feeds during manufacturing lead to losses in vitamin C. This leads one to question whether horses fed diets supplemented with raw Vitamin C are being fed the requirements. Microencapsulating the ascorbic acid particle provides a thin film, the size of the human hair around each particle and provides a stabilized vitamin C which can maintain its potency through manufacturing and during long term storage and thereby ensuring that the requirement for this vital nutrient is being met. Additionally, microencapsulation results in enhanced bioavailability of vitamin C.