Coggins tests are an important part of your horse's annual preventive care. Today, our San Angelo equine vets discuss why detecting Equine Infectious Anemia (EIA) is essential, and how Coggins testing is performed. 

Coggins Testing for Equine Animals

'Coggins' is the common name for an enzyme-linked immunosorbent assay (ELISA) which is a blood test used to screen horses, donkeys and mules for the potentially fatal disease Equine Infectious Anemia (EIA).

Equine Infectious Anemia - EIA

EIA is an infectious, potentially deadly virus that affects the immune system of animals in the Equidae family. 

It is possible for animals to carry the virus without showing symptoms (asymptomatic) however many horses suffer from severe symptoms of the disease including irregular heartbeat, weakness, swollen abdomen and/or legs, high fever, anemia, abortion in pregnant mares, or even sudden death.

A herd outbreak of EIA can lead to catastrophic consequences which is why it is essential for horse owners to be diligent about testing their equine animals for the condition.

How EIA is Spread

This potentially deadly disease is transferred from one horse to another through the bite of mosquitos, deer flies, horse flies or stable flies that have previously fed on an infected animal. This means that your horse does not have to come in contact with an infected horse in order to contract the disease. 

Since flies are attracted to barns and other places that horses frequent, this EIA can be quickly and easily transmitted from one horse to another.

What Happens When a Horse Tests Positive for EIA Antibodies

Once a horse has been infected with the virus that causes EIA they have it for life and are able to transmit the disease - via fly bites - to other horses nearby (anywhere within the travel range of the flies). For this reason, horses that test positive for Equine Infectious Anemia must either be euthanized, branded and strictly quarantined more 200 yards away from other horses for life, or transferred to a research facility.

Why All Horses Need a Coggins Test

The seriousness of EIA combined with how easily it can be transferred between animals makes regular Coggins testing for the disease our best defense for protecting the health of horses across the country.

Since many horses carrying the virus do not exhibit symptoms of the disease, testing horses with no symptoms of EIA is essential for detecting carriers and preventing further spread of the disease.

Coggins testing is required in both the United States and Canada when exporting horses across the border, and many states require testing in order to take horses across state lines.

A negative Coggins test is typically required before your horse can take part in competitions and events, and testing is highly recommended for all horses that spend time near other horses whether in fields or boarding stables.

The Coggins Testing Process

First, your veterinarian will give your horse a thorough physical examination to determine the overall health of your equine pet and to look for any signs of EIA. Your vet will complete an EIA form as they perform the examination which will include details such as your horse's coloration, marking, age and breed, and digital images will be taken of your horse.

Next, a blood sample will be taken from your horse which will be submitted to an accredited lab of analysis along with the EIA form and the images.

Once testing is complete the lab will forward your horse's test results either directly to you, and/or to your veterinarian.

Texas' Coggins Testing Regulations

All horses and other equine must meet Texas Animal Health Commission (TAHC) EIA testing requirements when changing ownership, participating in an assembly (rodeo, show, parade, etc), or stabled within the state of Texas.

  • Change of Ownership: All equine animals over eight months of age must have a negative EIA test within the previous 12 months, unless an exception applies.
  • Equine Assembly or Stabling: All Texas equine are required to have an EIA test within the previous 12 months when participating in any assembly of equine (rodeo, trail ride, parade, roping, etc.), enter a parimutuel track, or used for riding on publicly accessible equestrian trails or lands; or are housed at a boarding, training, or breeding facility.

To learn more about equine testing requirements in your area, or to determine if an equine animal qualifies for an exception, contact your equine veterinarian to request EIA testing.

Is it time for your equine friend to have a Coggins test? Contact the experienced vets at Western Veterinary Hospital today to book an examination and Coggins testing for your horse.