Evaluating Seasonal Effects on Diagnostic Test Results for Equine Cushing's Disease

An estimated 20 to 30 percent of the equine population is older than 15 years of age, and about one-third of older horses develop equine Cushing's disease, also known as pituitary pars intermedia dysfunction. Early diagnosis of the disease is critical because the condition is associated with significant health risks. The effects of season on the hormone responses to the diagnostic test currently used have never been evaluated, therefore, there are no seasonal reference ranges for diagnosing Cushing's in subclinical horses. Researchers will use the current test to evaluate hormone responses over a 12-month period in horses with and without equine Cushing's disease. This will allow them to determine if seasonal reference ranges are needed to accurately diagnose equine Cushing's disease early. Characterization of this test will allow for confidence in early detection of equine Cushing's disease and help prevent its progression