Endurance riding became an official Fédération Equestre Internationale (FEI) discipline in 1982 and has since been the organization’s fastest growing sport. Before, during, and after these long-distance rides veterinarians examine horses’ general attitude, metabolic state, soundness, and presence of sores, wounds, or other problems.

They might then eliminate horses (most often for lameness and metabolic reasons) if they don’t deem the horses fit to continue. However, very little evidence-based information exists on reasons and rates of elimination from competition.

Annamaria Nagy, DrMedVet, FRCVS, of the Animal Health Trust, in Newmarket, U.K., recently conducted the largest scale epidemiologic study of endurance rides and presented her findings at the British Equine Veterinary Association’s 51st annual Congress, held Sept. 12-15, in Birmingham, U.K.

In their retrospective study, Nagy and her colleagues documented the number of horses that started, completed, and then eliminated due to lameness or metabolic reasons at all FEI endurance events ranging from 100-160 kilometers per day (roughly 60-75 miles per day) between 2008 and 2011. They used data obtained from the FEI to evaluate risk factors for elimination as well as winning speeds