Just Say No to Poor-Quality Equine Supplements

Horse owners are becoming more and more discriminating when choosing nutritional supplements for their horses. Selecting high-quality, science-based products remains the best way for horse owners to fill nutritional gaps in diets, but it is often a challenging task that requires the assistance of an equine nutritionist and veterinarian.

A recent report highlighted the importance of supplement selection*. In that report, an eight-year-old Holsteiner gelding was provided a standard timothy hay-based diet augmented with a ration balancer and a blue-green algae dietary supplement to support hoof health.

Blue-green algae supplements reportedly also benefit joint health, yet horse owners have been warned repeatedly over the years to avoid ingesting algae—primarily via drinking water—because many types of algae produce potentially fatal toxins.

The above-mentioned horse was supplemented daily for two months with blue-green algae before suffering a sudden onset of jaundice, anorexia, depression, and colic. Within two days of admission to a local hospital, the horse declined rapidly and became recumbent with intermittent spurts of maniacal biting and circling that ultimately resulted in euthanasia.

The blue-green algae supplement offered to the horse was tested. Microcystin, a potent liver toxin produced by blue-green algae, was identified in two open supplement containers. The toxin was also identified in three of five unopened supplement containers. Because the toxin was not isolated from the horse’s liver, blood, or gastrointestinal contents, the authors presumptively diagnosed microcystin as the cause of death.

Nonetheless, this case report underscores once again that choosing a quality supplement is imperative for the safety of your horse. Equine nutritional supplements are not manufactured like pharmaceutical drugs (i.e., using quality control standards) and are only loosely regulated by the Food and Drug Administration (FDA) due to their low standing on the FDA’s priority list. As a result, nutritional supplements fall into the “buyer beware” category.

How do horse owners avoid tainted products?

Look for reputable companies with science supporting their products rather than relying on testimonials alone. For example, Kentucky Equine Research (KER) offers Bio-Bloom PS (Bio-Bloom HF in Australia) to support hoof health. This product contains key ingredients, such as methionine, iodine, biotin, and zinc, that are shown by scientific studies to benefit various skin and hoof conditions. KER is is also certified by FAMI-QS, an international quality and safety certification system for the animal feed industry, as well as other governing agencies.

*Mittelman, N.S., J.B. Engiles, L. Murphy, et al. 2016. Presumptive iatrogenic microcystin-associated liver failure and encephalopathy in a Holsteiner gelding. Journal of Veterinary Internal Medicine. 30(5):1747-1751.