Officials from the USDA’s National Center for Import/Export recently rescinded a contagious equine metritis (CEM) exemption once given to Spanish purebred horses. The exemption allowed these horses to pass through the import center with an abbreviated form of CEM testing, an allowance that was revoked due to repeat violations of U.S. equine import requirements.

Contagious equine metritis is a highly contagious venereal disease that often causes no clinical signs in mares or stallions. It is caused by the bacterium Taylorella equigenitalis. The stallion acts as a carrier of CEM, which is passed along to mares and can affect fertility. Rigorous treatment is required to rid horses of the bacterium.

Under current regulations, the USDA’s Animal and Plant Health Inspection Service (APHIS) requires that stallions and mares over the age of 731 days coming into the United States from CEM-affected regions for permanent import (they aren’t in the U.S. temporarily for competition or breeding) go through routine tests for specified diseases, a three-day quarantine, and remain under observation for signs of illness. Then they are transported to an approved CEM quarantine facility, where they undergo additional testing and observation for up to 30 days.

The exemption had applied to Spanish purebred horses (any horse certified by the Spanish government as such), typically Andalusians. It had been negotiated with Spain that horses with paperwork that certified they had not been bred or kept on a premise that is exclusively a breeding premise would be exempt from post-import CEM quarantine and testing (however, prior to entry, three negative swabs for CEM were required). The regulation was published Aug. 1, 2000, said Freeda E. Isaac, DVM, staff veterinarian at the National Center for Import/Export. “You would not have to do a full CEM (inspection and quarantine) after entry for stallions and mares coming from Spain