pelleted supplement
Many horses receive medications or nutritional supplements to help manage joint discomfort associated with the prevalent joint disease osteoarthritis (OA). | Photo: Jennifer Whittle/The Horse
Many horses receive medications or nutritional supplements to help manage joint discomfort associated with the prevalent joint disease osteoarthritis (OA). Some therapies designed for arthritic horses can be irritating to the stomach wall, potentially contributing to gastric ulcer development.

Per North American Supplement Council (NASC) regulations, joint supplements containing turmeric and devil’s claw, for instance, must have a caution on the label stating that these products can be gastrointestinal irritants.

During a presentation at the 2020 American Association of Equine Practitioners’ Convention, held virtually, Michael St. Blanc, DVM, from Louisiana State University’s School of Veterinary Medicine, said such warnings raise the question of whether turmeric and devil’s claw contribute to the worsening of gastric ulcer scores in supplemented horses.

“If they do not, then supplements containing these ingredients would be an attractive alternative to pharmaceutical medications known to be gastrointestinal irritants, such as non-steroidal anti-inflammatory drugs such as phenylbutazone, or Bute,” St. Blanc said.

Both turmeric, a member of the ginger family, and devil’s claw, from the sesame family, reportedly have anti-inflammatory properties. Turmeric also exerts free radical scavenging activities.

To test the hypothesis that these nutritional supplements would not increase a horse’s ulcer score, St. Blanc and colleagues recruited 12 horses with pre-existing equine gastric ulcers. They randomly assigned those horses to either a supplement or control group. Horses in the supplement group received two supplements combined in a top-dress formulation, containing a cumulative amount of 12,000 milligrams of turmeric root powder and 2,500 milligrams of devil’s claw extract per treatment. Horses in the control group received top-dressed supplements containing only the inactive ingredients found in the treatments. These diets were fed once daily for a total of 28 days.

Horses underwent gastroscopies on Days 0, 14, and 28 of the study to measure gastric ulcer scores. The research team found that gastric ulcer scores decreased in all study horses, with no significant difference between treatment and control horses.

“The decrease in ulcer score in all horses in the study could be due to the change in management of the horses once they were enrolled in the study,” St. Blanc said. “Regardless, there was no worsening of gastric ulcers in the treated horses. The tested products had good palatability and were well-tolerated by the horses,” making them a potentially safe component of OA management.