Colorado Mare Tested for CEM

One Colorado mare has been identified as having been in contact with a stallion infected with contagious equine metritis (CEM). A hold order has been placed on the premises until tests results have returned.

"Colorado is now among 27 other states tracing horses and testing for this disease," said Keith Roehr, DVM, Colorado Department of Agriculture's state veterinarian. "It is important to remember that this disease does not affect humans and CDA is working quickly to determine whether this mare is infected."

CEM is a highly contagious venereal disease, which can result in temporary infertility. The disease can be transmitted by live cover or artificial insemination and can be treated with antibiotics.

"Breeders need to be cautious when shipping a horse out of state for breeding purposes and bio-security measures are vital to preventing the spread of this disease," Roehr said. "All equipment should be sanitized when collecting semen for artificial insemination."

If the test results are positive for CEM on the Colorado horse, she will be required to undergo treatment and remain in quarantine for no less than 21 days.

CEM is a foreign animal disease; prior to this outbreak, which was first discovered in Kentucky in late December, the U.S. was recognized as a CEM-free country. Federal, state, and private practicing veterinarians are working with the equine industry in a timely manner to regain national CEM-free status.

States that have so far announced CEM exposure:

  • Colorado
  • Indiana
  • Kentucky
  • Montana
  • North Dakota
  • Oklahoma
  • Texas
  • Virginia
  • Wisconsin
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