President Eric Hamelback gave a sense of urgency as he opened the most recent meeting of the Kentucky Thoroughbred Farm Managers’ Club, saying “we need to make plans for control now.” Hamelback was referring to Mare Reproductive Loss Syndrome, an affliction which caused early and late fetal loss in Central Kentucky in 2001 and 2002, and was also the subject of the Nov. 5 meeting in Lexington, Ky.

Research this year has pointed to Eastern Tent caterpillars as the causal agent of MRLS, although the way the caterpillars turn their presence into a deadly force is still undetermined. In an effort to prepare for 2003, the KTFMC solicited input from two veterinarians, a farm manager, and an entomologist to encourage proactive behavior.

The most useful information came from Dr. Lee Townsend, an entomologist with the University of Kentucky. Townsend explained that horse and farm owners can eradicate caterpillars by spraying the foliage they eat with chemicals like Talstar or Dipel, or by “inoculating” their preferred hosts, wild cherry trees. Inoculation requires more training or hiring professionals, but Townsend said when the chemical Bidrin was used with that method, it killed 99% of young caterpillars.

Townsend stressed that early intervention, i.e. killing caterpillars while they are still young, is imperative to keeping their effects to a minimum. Caterpillars congregate in trees in the spring, stripping them of foliage and maturing, before leaving trees in search of more food. At that point they are much more likely to come in contact with horses