What is a Coggins test?
A blood test that detects antibodies to equine infectious anemia virus in horses, required by Colorado law for interstate movement and sale.
The Coggins test is a laboratory blood test used to identify equine infectious anemia (EIA) in horses. The test detects antibodies produced when a horse is infected with the EIA virus, which is spread through blood-to-blood contact, primarily via biting insects like horseflies and mosquitoes.
Colorado law requires a negative Coggins test result before a horse can be transported across state lines, sold, or entered into certain facilities. The Colorado Parks and Wildlife Division enforces these regulations to prevent the spread of EIA, a disease that can cause fever, weight loss, and anemia in infected horses. A positive result means the horse carries the virus and cannot legally travel interstate or be sold in Colorado, though the horse may remain on its home property under specific conditions.
The test must be performed by a licensed veterinarian and results are registered with the USDA's National Equine Health Registry. Results are typically valid for 12 months. For horse owners in the Denver area planning to travel, sell, or move their animals, a current negative Coggins test is a legal prerequisite. Many equine veterinarians in Colorado offer the test as part of routine health screening and can advise on state-specific requirements.