Latest Numbers Presented on Late Term Abortion/Early Foal Loss Syndromes

The University of Kentucky Disease Diagnostic Center reported Thursday that a total of 386 aborted/stillborn equine fetuses/foals had been submitted for diagnostic testing/evaluation since the problem first arose late last month.

The latest numbers and other information about the syndromes were presented to the Kentucky horse industry and veterinary community Thursday during an informational session at the Keeneland Association sales pavilion in Lexington, Ky. There was a standing-room only crowd at the informational session sponsored by the Kentucky Thoroughbred Farm Managers Club and the Kentucky Association of Equine Practitioners.

As of noon Thursday, May 10, an additional 15 aborted/stillborn equine fetuses/foals were submitted for diagnostic testing/evaluation, according to the diagnostic center. That brings the total count to 386 since April 28. As of noon, Tuesday, there had been 318 aborted fetuses/foals submitted for testing and evaluation.

While the number of fetuses/foals being sent to the center has tailed off in recent days, Dr. Doug Byars cautioned that it does not necessarily indicate the problem is abating or is check. He noted that the fewer numbers may be more indicative of the fact the breeding season is also nearing its end.

As an additional reflection of the magnitude of the problem, Dr. Roberta Dwyer presented results of a questionnaire sent to sent to 270 farm managers. Based on responses from 159 farms received as of Wednesday morning, May 9, there were 37 farms which had no early fetal/foal loss. On the other end of the spectrum, 17 farms had more than 50% fetal/foal loss.

Dwyer reported there were 3,294 mares fitting the questionnaire criteria of having been checked in foal at 42 days. Of those, 2,616 were still in foal on May 8, for a 79% in foal rate.

Dr. Lenn Harrison reported that the diagnostic center has received specimens from 18 different breeds, with about 70% being Thoroughbreds. Results from the 247 necropsies completed indicate the problem does extend from early to late in a mare's pregnancy status, Harrison said.

The necropsies also indicate there is not a viral component to the syndrome t this time, and that "bacteria probably plays a vital role in the syndrome."

In addition to the problem of aborted/stillborn foals and fetuses, Byars said veterinarians are also "seeing illnesses in other genders and age groups in larger than normal numbers."

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