Getting to the bottom of GI health in dog athletes

New research from the University of Minnesota College of Veterinary Medicine (CVM) shows stomach acid suppressants given to sled dogs before a race may not prevent gastrointestinal (GI) injury, as previous research has suggested. 

GI injury is common in both canine and human athletes. Exercise can cause sores to form in the inner lining of the stomach, intestines, and colon and trigger systemic inflammation that affects the gut. These erosions and inflammation can compromise an athlete’s performance and cause a host of GI symptoms including diarrhea and vomiting, and can sometimes be fatal. Omeprazole—an over-the counter acid suppressant—is commonly given to sled dogs before a race to prevent this from happening. 

Dr. Tracy Hill, an associate professor of internal medicine at CVM, led a team of researchers who measured gastric erosions in a team of nine Alaskan sled dogs. 

Starting the day before the 2019 Copper Basin 300 race, a nearly two-day, 263-mile sled dog race in southeastern Alaska, where temperatures regularly hover around -60 degrees Fahrenheit, each dog was given a daily dose of 1 mg/kg of omeprazole, which continued until the race ended. Dr. Hill’s research team then took blood samples from each dog 8–10 hours before and after the race and used the samples to detect cytokines, which indicate systemic inflammation and could serve as a marker that would tell the researchers to what degree each dog suffered intestinal injury. They also used video capsule endoscopy—a vitamin-sized wireless camera that takes continuous video of the lining of the digestive tract—to detect damage post-race. 

Eight of the nine dogs had gastric erosions, which occur in the stomach, and all nine had small intestinal erosions, despite not showing any signs of GI bleeding, a finding that surprised Dr. Hill. It brings into question what the best treatment would be to prevent gut injury in canine athletes.

Since the researchers did not measure lesions beforehand, it’s unclear if some were present before the race began. Most of the dogs had foreign materials like straw or bits of gravel present in their GI tracts as well, suggesting that this may also have contributed to the damage. Until more is known, Dr. Hill and her colleagues are recommending that the current therapies still be used, since past research as well as anecdotal reports show that the rates of serious injury and death are lower when sled dogs take omeprazole. 

The study clearly showed that gastric injury is common among sled dogs following a race, and future research will need to determine how common lesions are, whether or not exercise is the main cause, as opposed to other things such as chewing on sticks, and what treatments may be better treatments than omeprazole . For now, it’s safe for dogs to take omeprazole to prevent some GI issues during or after a race, but future studies will need to document each dog’s lesions before the race and compare them to the severity and number of lesions after they’ve finished, and compare whether or not taking omeprazole made a difference. What researchers discover in dogs may one day apply to people, too.

“Exercise-induced gut syndrome is likely similar in dogs and people,” said Dr. Hill. “If we are able to continue funded work in the field of working dogs, we would hopefully be able to find effective preventative strategies that could be applied for people as well.” 

Read the full study in The Journal of Small Animal Practice.