Neurologic Disease Prevalence in Necropsied Horses

Horses can show neurologic signs—stumbling, incoordination, dull or depressed attitude, behavioral changes—because of many health conditions. When researchers at the University of Kentucky Veterinary Diagnostic Laboratory examined equine necropsy records for 2011 and 2012, they found that 88 horses had been given a clinical diagnosis of neurologic disease. This problem was seen in 2.2% of necropsied horses in 2011 and 3.1% in 2012.

Cervical vertebral stenotic myelopathy, also known as wobbler syndrome, was the most common finding, accounting for 42 of the 88 horses studied. Wobbler syndrome occurs when abnormalities of the vertebrae in a horse’s neck cause compression of the spinal cord. This condition was somewhat more common in males (86% of affected horses in this study) than in females, and is usually found in horses that are under the age of three (36 of 42 horses). Affected horses included Thoroughbreds, Quarter Horses, American Saddlebreds, Standardbreds, and Tennessee Walking Horses.

The most commonly found infectious disease was equine protozoal myeloencephalitis, with 12 cases in 2011 and 18 cases in 2012. Horses ranged from a yearling to a 20-year-old mare and were of several different breeds. A few cases of West Nile virus and equine herpesvirus were also found.