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Veterinary Science	Mare Reproductive Loss Syndrome Index Page
Briefings

Mare Reproductive Loss Syndrome

Briefing, June 8

Briefing, June 8, 2001
Friday, 5:00 pm

Mare Reproductive Loss Syndrome
UK College of Agriculture

MRLS Update

On June 6 a meeting was held with a number of equine veterinarians who have been involved with heart and eye problems that may be associated with MRLS.  Approximately 50 cases of each condition have been identified to date involving a wide age range of horses and breeds.  These cases are not necessarily associated with mares that have experienced early or late fetal losses.  Twelve necropsy cases of pericarditis have been examined at the Livestock Disease Diagnostic Center.  The eye condition observed is unilateral, and never bilateral.  A wide range of tests have been performed and further tests are underway to identify the cause of these conditions and clarify the link to MRLS.

Detailed investigations are underway to prove or disprove the possibility of cyanide as the cause of MRLS.  In addition, the investigation of other possible causes including mycotoxins, fungal endophytes, phytoestrogens, chemical compounds and infectious agents is still underway, although results to date provide no evidence that they are involved in the cause of MRLS.

The 23 member MRLS survey team spread throughout central Kentucky from Danville to Carlisle, Springfield to Simpsonville, and Lexington to Louisville searching for information.  Farms managers with 20 to 300-plus mares were interviewed and willingly shared farm statistics and management practices with team members.  Thoroughbred, Standardbred, American Saddlebred and Morgan horse farms have been surveyed in multiple counties.  As of 10:00 AM June 8, over 130 surveys have been completed and returned to survey coordinator, Dr. Roberta Dwyer.  This rapid response in obtaining the quality and quantity of information during such a busy time of year indicates the dedication that the equine industry has in assisting the research effort.  Data entry has been in progress, and an in-depth analysis will begin once all data has been verified and processed.  The goal of this in-depth survey is to identify risk factors on horse farms for early fetal loss and/or late term abortions, and to provide additional clues to the diagnostic investigation.