A healthy respiratory system is essential to every horse's well-being and athletic performance. Like humans, horses rely on their lungs and airways to deliver oxygen throughout the body, but the demands placed on their respiratory system increase dramatically during exercise. Efficient oxygen exchange allows working muscles to perform, while the respiratory tract also serves as an important defence system by filtering and removing dust, bacteria, ammonia, and other airborne irritants. Although mucus, coughing, sneezing, and nasal discharge help clear the airways, excessive amounts of these signs may indicate an underlying respiratory problem.

Davis, CA, May 29, 2026 — Researchers at the UC Davis Weill School of Veterinary Medicine, led by Dr. Carrie Finno and graduate student Briana Brown, have reported the genetic cause of a fatal neurologic disease, equine juvenile spinocerebellar ataxia (EJSCA), in American Quarter Horse foals. A genetic test is available through the UC Davis Veterinary Genetics Laboratory (VGL).

West Nile virus (WNV) is a mosquito-borne virus that affects humans and other animals, of which horses represent 96.9 percent of reported non-human cases. Introduced to the United States in 1999, WNV is now found in all of the contiguous 48 states.

What Every Horse Owner Should Know - As summer arrives, veterinarians and horse owners across Canada grow increasingly concerned about Potomac Horse Fever (PHF). Once rare, the disease is appearing more often in regions north of the United States. Potomac is now considered endemic in Ontario, Quebec, Nova Scotia, Manitoba, Alberta, and British Columbia.