Can Vitamin B-12 Improve a Horse’s Appetite?
Vitamin B-12, or cobalamin, plays several vital roles, including the central nervous system as it aids in the synthesis of myelin the material that coats nerve fibers, fatty acid, and amino acid metabolism and red blood cell maturation in bone marrow.
Vitamin B-12 is a water-soluble vitamin. Water-soluble vitamins aren’t stored in the body, so it’s hard to overdose if supplementing them, because they’re rapidly excreted in urine. That said, unlike other water-soluble B vitamins, vitamin B-12 can be stored in the body in small amounts but not at levels that cause problems with additional supplementation.
Vitamin B Deficiencies in #Horses are Rare
Thanks to the plant-based nature of the horse’s diet and the large hindgut bacteria population, vitamin B deficiencies are considered rare. In fact the only B vitamin requirements the National Research Council notes in its Nutrient Requirements for Horses are thiamin and riboflavin. Thiamin has a requirement due to research with two horses fed purified diets for 16 weeks that showed deficiency symptoms and other research where increased growth rates and appetite occurred in horses fed additional thiamin. Riboflavin has a dietary requirement based on some limited research suggesting that horses fed additional riboflavin saw improved growth. However, there are no controlled studies that show dietary requirements for the other B vitamins above what’s produced in the equine gastrointestinal tract. The NRC requirements for thiamin and riboflavin are easily met by the diets typically fed to horses.
So, What About B12
Vitamin B-12 is somewhat unique in that is does not exist in plants. It’s synthesized by the gut bacteria, a process that requires the trace mineral cobalt. Research has shown that supplementing 15 milligrams of cobalt chloride has an impact on serum and fecal vitamin B-12 levels.
While no scientific evidence shows that a dietary requirement for B-12 above that supplied by intestinal synthesis exists, there are times where supplemental B-12 might benefit horses, and certainly owners report that they believe seeing a benefit in some horses. Obvious times to supplement would include when the hindgut microbial population—and thus B-12 synthesis—is or could be disrupted.
Examples of possible disruption would be after antibiotic administration, long-term non-steroidal anti-inflammatory drug use, dietary changes, diarrhea, high-intensity performance training, and general ill health or reduced appetite.
Supplementation can also benefit young horses with incomplete hindgut microbial population and very old horses who appear to have reduced digestive capacity.
A Look at Research in Humans
An interesting consideration from the human literature is that there’s some limited evidence that long-term use of acid suppressants such as proton pump inhibitors (omeprazole) and histimine-2 receptor antagonists (such as ranitidine) might decrease B-12 absorption. This is because B-12 requires stomach acid to be absorbed. Providing gastric ulcer treatment to horses is unlikely to have an impact on vitamin B-12 status, because horses’ needs are met from B-12 production further down the digestive tract. However, it could impact the ability to fully utilize supplemental B-12 sources.
While it is possible to buy supplemental B-12 sources, it might be more effective to supplement with a full range of B vitamins. This is because the other B vitamins are also made in the horse’s hindgut by the bacteria, so if there are problems with gastrointestinal B-12 production it stands to reason that the production of other B vitamins might also be affected.
Brewer’s yeast is a good broad-spectrum source of B vitamins; however those levels of the B vitamins might be inconsistent. For that reason a good quality commercial B vitamin supplement might be a better option because levels should be guaranteed.
Source thehorse, 8 July 2018