Horses on hay alone or that receive supplementary commercial feed mixed with oats, for example, might not be getting adequate calcium if they’re also being treated for gastric ulcers. | Photo: iStock

Researchers have found that horses treated for gastric ulcers could be getting less calcium into the bloodstream than they would normally. Depending on the calcium source, horses treated with omeprazole (such as GastroGard, the FDA-approved medications for the treatment and prevention of equine gastric ulcers) could be digesting 15-20% less calcium than when they’re not on omeprazole.

Over prolonged treatment periods, this could lead to deficiencies if the horse isn’t consuming adequate amounts of calcium, said Joe Pagan, PhD, founder of Kentucky Equine Research (KER), in Versailles.

“The vast majority of commercial feeds include sufficient quantities of calcium for working horses to cover the horse’s calcium needs, even if he’s not digesting the full amount due to omeprazole,” said Pagan. “But that means following the feeding instructions on the labels to be sure the horse is getting the correct