Ga Dept of Agriculture


Contagious Equine Metritis (CEM) FAQs

What is CEM?
CEM is a treatable, non-fatal, venereal disease of horses caused by the bacteria Taylorella equigenitalis. Transmission occurs during breeding, both natural service (live cover) and artificial insemination. Additionally, the bacteria can be spread by contaminated hands or other objects such as instruments. CEM is considered a foreign animal disease (FAD) as it is not normally found in the U.S. CEM does not present a disease risk to humans or animals other than equine.

What are the clinical signs of CEM?
Stallions do not show clinical signs but can carry and spread the disease (inapparent carriers). In mares, initial exposure usually results in temporary infertility. Rarely, abortions occur. Infection can progress and cause uterine inflammation or infection with a thick, milky, mucoid vulvar discharge. Discharge is typically most apparent 10-14 days post-breeding. Mares can also become inapparent carriers.

When will hold on horses undergoing CEM testing be released?
The Georgia Department of Agriculture issues and releases CEM holds or quarantines.  Horses undergoing CEM investigation and testing will be released if epidemiological evidence indicates no exposure, or when all appropriate testing and treatment are concluded.  

When can I export semen from a CEM exposed stallion?

Requirements must meet the importing country requirements.  Once all testing is complete and the quarantine has been officially lifted, the normal protocols for export can commence.
Note: The time spent quarantined for CEM does not count toward pre-export isolation/ quarantine, when required.

How could having a CEM exposed horse at a semen collection facility or holding center (i.e. farm or barn) affect export of semen from non-exposed horses?
Product (semen) must meet the importing country requirements. Semen collected while a CEM exposed horse is (or has been) on the premises is considered potentially positive until laboratory testing confirms that the exposed horse is negative for CEM and the animal has been officially released from quarantine. Non-exposed stallions that are cohorts with a potentially exposed stallion undergoing CEM testing may have to wait to begin pre-export requirements for semen export until:

  • The exposed stallion completes all testing/treatment and is officially quarantine released.
  • The exposed stallion is removed from premises (before testing is completed).

Note: It may be possible for the exporter to obtain a waiver from the importing country that indicates it will allow semen from a center where an animal is presently quarantined for exposure to CEM.

Is frozen semen stored at a facility under CEM investigation subject to export restrictions?
Product (semen) must meet the importing country requirements.  In many cases, semen collected prior to the 2008 breeding season can be exported as long as the donor stallion met all testing requirements at the time of collection. This applies to both exposed animals and any other susceptible animals co-located at the holding center or collection facility. Semen collected from certain exposed and co-located stallions in the 2007 breeding season may also be subject to export restrictions. Please contact state or federal authorities for case-by-case information.

USDA APHIS- Contagious Equine Metritis

USDA APHIS- Import of Horses or Equine Semen from Countries Affected with CEM

USDA APHIS- Import of Horses or Equine Semen from Countries Affected with CEM over 731 days

Kentucky Department of Agriculture- Equine Program

Iowa State University CVM- Contagious Equine Metritis Fact Sheet

Canadian Import Regulations

CEM must be reported immediately upon diagnosis or suspicion of the disease.
Federal: GA Area Veterinarian in Charge (AVIC): 770-922-7860
State:  GA State Veterinarian: 404-656-3671