Introduction Stallion Services Mare Services Education On-Farm Services

Dear CEM Quarantine Survivor,

   First let me say that you have my deepest sympathies for having gone through the whole ordeal of CEM quarantine testing with your facility and/or horse(s).  At your expense, the industry has learned a great deal from this 2008/2009 outbreak.  The first of which this disease does not seem to be nearly as transmissible as once thought.  In 1977 and 1978, contagious equine metritis (CEM) spread readily throughout Thoroughbred breeding farms primarily by way of natural service conditions.  Because it was a new disease at that time, nobody was familiar with its presence, degree of transmissibility, clinical symptoms or effective methods of treatment.  Trying to understand and effectively deal with the disease led to farms being placed under quarantine, which abruptly halted the breeding season for many. 

   The outbreak over 30 years ago had significant clinical and financial ramifications on the Thoroughbred industry so leaders of the profession subsequently assisted the United States Department of Agriculture in creating regulatory guidelines for testing breeding stock coming into the U.S.  The goal was to maintain the U.S. as a CEM-free country thus classifying the causative bacteria, Taylorella equigenitalis as a foreign-borne organism which originated from the United Kingdom.  This status was effectively in place until December of 2008 when a Quarter Horse stallion in Kentucky tested positive for this bacteria after a routine culture was performed in preparation for semen exportation. This surprised many because this stallion had not previously been out of the country and thus questions were raised as to how he acquired the organism if it truly was eradicated from the U.S. years prior.  Subsequent months of a trace-back investigation originally pointed to a single-source stallion that came into the U.S. from Denmark in 2000.  Currently however, officials are saying that the introductory source has not been conclusively determined.  Of course as you know, in the tedious process of tracing back the origin of how this organism reentered this country, many horses and facilities were put under quarantine and underwent testing protocols.  The testing of 276 stallions resulted in the identification of 22 stallions that cultured positive for Taylorella equigenitalis.  Those stallions bred and/or exposed 715 mares to this bacteria of which 5 tested positive. 

   What this exhaustive and expensive trace-back investigation taught us was that this organism more than likely was in the U.S. for many years without detection.  It was not detected because unless a horse or semen is coming into or out of this country, no culturing for Taylorella equigenitalis is required or performed.  In addition, there were no clinical indications, either by increased numbers of mares with unique vaginal discharge and/or decreased pregnancy rates, that a significant venereal outbreak was even out there.  Because of this, the question now raised is “should there be more or less governmental regulation on the detection of this organism?”  Some practitioners believe that if there were more regulatory oversight in place at the state level for culturing animals then the most recent outbreak would have affected less people and horses.  In contrast, other practitioners look at the data collected thus far from this latest occurrence and conclude that with all that we know about the CEM-causing bacteria, there should be less governmental involvement on its regulation.  Their position is supported by the fact that this organism was in the industry for years and did not result in any significant CEM outbreak.  Since most of the exposed mares were bred via artificial insemination, the transmissibility of Taylorella equigenitalis was greatly reduced (0.7% degree of transmissibility).  It has been and can be readily managed through normal private industry standards of practice.  In addition, if one animal does culture positive for the organism, it’s hard to justify going through the economic impact of a USDA-regulated quarantine and trace-back investigation when this organism can be effectively treated in the stallion and mare with no long-term ramifications on the horse’s health or breeding endeavors. 

   We are at a pivotal point in our industry on deciding what role the USDA and/or state governmental agencies should have with respect to CEM regulation.  We must remember that this is a treatable disease that is solely venereal in nature.  It does not affect the horse’s overall health and has no affect on other species or the country’s food source.  For these reasons, the current governing bodies are open to modifying and/or reducing their role as the “supervisory entity” if there is a general consensus from the horse industry that such an action is justified.  Therefore, I ask that you click on and complete the CEM Survey Form below.  The completed form can be returned via email, fax or regular mail.  This will help the industry understand how the 2008/2009 Taylorella equigenitalia outbreak and subsequent USDA involvement affected you and your business.  Also, if you know of others (stallion and mare owners, farms, clinics, etc.) that have been affected by this situation, please forward their contact information or have them get in touch with me.  It is vitally important that we get as much client participation as possible. Comprehensive involvement will effectively impact the issues being reevaluated such as regulatory roles of the government vs. private industry, quarantine and treatment guidelines, financial reimbursement for outbreak investigations, etc.  It would be remiss if we didn’t learn from this latest outbreak and reassess how the regulations can better suit the industry.  Thank you very much for your cooperation. 

Kevin D. Dippert, PhD, PAS
Equine Reproduction Concepts, LLC
111 Hackleys Mill Rd.
Amissville, VA 20106
Telephone: 540-937-9832

CEM Survey

Download and print the CEM Survey

topBack to Top
"All veterinary services are performed by a licensed veterinarian"

111 Hackleys Mill Rd. Amissville, VA 20106
(Phone) 540-937-9832 (Fax) 540-937-9862

Copyright © 2019 Equine Reproduction Concepts, LLC. All Rights Reserved.