03/30/2004 12:00AM

Fight against MRLS advances


Two University of Kentucky entomologists gave local horsemen some practical advice and research updates in the fight against mare reproductive loss syndrome Tuesday.

In a meeting at Keeneland organized by the University of Kentucky and the Grayson-Jockey Club Research Foundation, which has funded studies into the abortion-causing disease, professors Ken Haynes and Don Potter acknowledged that researchers still don't know exactly what caused the mare reproductive loss syndrome that caused thousands of mares to abort in central Kentucky in 2001 and 2002. But based on current research, they believe the Eastern tent caterpillar is the culprit, even if its exact disease-causing mechanism is unknown. With the caterpillars' silky, tent-like nests already beginning to appear in Kentucky's trees, Potter recommended that breeders and farm managers spot-treat the nests while they are small with such insecticides as Talstar or Dipel, both of which UK researchers have found effective, or by injecting systemic pesticides into tree trunks. Once caterpillars have defoliated their host trees and begin moving in search of new food sources, Potter said, they can be stopped by spraying a six-foot barrier zone of the insecticide Astro around tree trunks and outside fence lines.

In his presentation, Haynes described UK's research into Eastern tent caterpillar pheromones, which might yield effective traps for the moths that produce the caterpillars. Haynes also monitors the annual population cycles of Eastern tent caterpillars in order to develop an early-warning system to alert mare owners when a major infestation is about to occur. Potter and Haynes said that this spring is not expected to produce a high infestation of the insects.