What is a Coggins test?
The Coggins test is a blood test that detects antibodies to equine infectious anemia virus, required by Colorado law for horse transport, sale, and boarding.
A Coggins test screens for equine infectious anemia (EIA), a contagious viral disease in horses. The test detects antibodies in a horse's blood sample using a laboratory technique called an agar gel immunodiffusion test. A licensed veterinarian collects the blood, and results determine whether a horse carries the EIA virus.
In Colorado, a current Coggins test certificate is legally required before moving a horse across state lines, selling a horse, boarding at most facilities, or participating in organized events. The test is valid for one year from the collection date, though some states and events may require more frequent testing. A negative result confirms the horse is free from EIA and can travel; a positive result means the horse is infected and cannot be transported to other states or sold without written consent from Colorado Parks and Wildlife.
The Coggins test protects the equine industry by preventing the spread of a disease that causes fever, weight loss, and anemia in affected horses. Since there is no cure for EIA, early detection through regular testing is critical for herd health. Large-animal and equine veterinarians in the Denver area perform Coggins tests as a standard service for horse owners needing compliance documentation.