About 200 people gathered at an April 6 meeting at the Ocala Breeders’ Sales Co. pavilion in Ocala, Fla., for an update on mare reproductive loss syndrome (MRLS). The syndrome is believed to be responsible for at least three equine deaths in Alachua and Marion Counties. According to most theories, MRLS results from pregnant mares ingesting Eastern tent caterpillars (ETC). Complications of MRLS include late-term abortions and early-term fetal losses in mares recently bred.

At least one Ocala area farm reduced the chance for MRLS to strike its stock, shipping pregnant mares elsewhere.

Speakers from the University of Florida (UF) said MRLS has probably been the cause of random equine deaths in Florida for years. John Roberts, DVM, Dipl. ACVP, who last year came to the UF from the University of Kentucky Livestock Disease Diagnostic Center, performed about a fifth of all necropsies in the Kentucky MRLS outbreak in 2001 and 2002. He said the first Florida case he saw in March 2006 clearly was MRLS. The mare was being kept at a farm that had both ETC and cherry trees. She delivered a septic foal March 18 that showed the telltale sign of MRLS–a crusty, yellow umbilical cord.

As of May 2, there had not been any additional reports of MRLS in Florida