MRLS Effects Minimal in Central Florida

By Ryan Conley
The impact of the deadly mare reproductive loss syndrome has been minimal on central Florida horse farms this year, but experts say steps should be taken to limit future problems in the area's vast equine industry.

That was the theme of an informational meeting held Thursday at the Ocala Breeders' Sales Co. pavilion, where about 200 people gathered to hear discussion on MRLS, which in March officially surfaced for the first time in Florida, and is 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. Complications of MRLS include late-term abortions and early-term fetal losses in mares recently bred back to stallions.

Speakers affiliated with University of Florida veterinary and entomology programs told the audience that MRLS has probably been the cause of random equine deaths for countless years.

But it took a diagnosis from a pathologist who was on the front-line of the devastating Kentucky outbreak of 2001-2002 to make MRLS official in the state of Florida.

Dr. John Roberts, who last year came to UF from the University of Kentucky Livestock Disease Diagnostic Center, said the first Florida case he saw in March was clearly a case of MRLS.

The mare, which was part of the UF breeding herd, was being kept at a farm that had both Eastern tent caterpillars and cherry trees, which are the preferred nesting spot for the pests. The mare, which delivered a septic foal March 18, exhibited the telltale sign of crusty, yellow umbilical cord.

"It's about the only syndrome that does this so acutely," said Roberts, who was involved in about a fifth of all necropsies performed on horses in the Kentucky outbreak.

Roberts said the amount of Eastern tent caterpillars in central Florida was nowhere near the large population found in Kentucky during its bout with MRLS. He displayed a photo taken at the time that showed a bucket filled with the caterpillars.

"I assume what you have here now is about the normal amount of caterpillars," he said.

While admitting his opinion might be a bit controversial, Roberts also said he isn't sure that MRLS is restricted only to Eastern tent caterpillars, which are active in spring months. He feels a septic foal brought to UF by a farm in nearby Pasco County last September was possibly afflicted with MRLS.

"There were an incredible number of walnut caterpillars at the farm," he said of the variety that frequent walnut, pecan, and hickory trees. "And trees that should have been filled with leaves were defoliated."

Some farms near Ocala, Fla., had already taken steps to reduce the chance for MRLS to strike their stocks. Eugene and Laura Melnyk's Winding Oaks Farm shipped out 43 mares and 16-20 foals to Three Chimneys Farm and Claiborne Farm in Kentucky. Some of the mares had just recently returned from Kentucky after being bred back to stallions there.

"It was quite expensive to do what we did," said farm manager Phil Hronec, who had seen several caterpillars on the 1,000-acre Winding Oaks property. "I might not have done it had I attended the seminar first. But we didn't want to take any chances. Eugene said, 'I don't want to lose even one horse to a caterpillar.' It was a no-win situation for us."

Workers at Anne and Satish Sanan's Padua Stables were dispatched by horse operations manager Bruce Hill to search for caterpillars and cherry trees on the 800-acre farm. They found just a handful of each.

"When you find a half-dozen (caterpillars) on 800 acres, there is no reason to panic," said Hill of Padua, which is home to about 100 mares. "But we are always going to be aware of them. And we will take out all of the cherry trees we can."

Wild cherry trees, which unlike traditional ornamental types, are tall, spindly and don't always bear fruit, are in abundance in Marion County, a horticulture professor at Central Florida Community College said.

"You and I could walk for five minutes, and I could show you 15-20 in the area of the college," said professor Robert DuMond. "They are everywhere, and I am sure they line many farm properties. If it is a problem in the equine industry, people should be able to identify them."

Dr. Judy Downer, a horse owner and breeder who also heads up the equine studies program at CFCC, was among those who found the seminar beneficial.

"I think that being informed about MRLS is the best thing that Marion County horsemen can do," she said. "Being informed doesn't mean panic, however. It means understanding the disease and taking appropriate steps to protect your horses."