State agriculture officials plan to meet with the owners of a Gorham horse farm Tuesday to outline options for disposing of 23 horse carcasses that died of botulism over a three-week period last month.

State veterinarian Don Hoenig said he plans to present Anne and William Kozloff with a letter describing the two options.

The preferred method would be to compost the remains, a process that would cause soft tissues to decompose within three months, and the long bones after about six months.

However, the 23 horses are already buried about 8 feet deep at the Whistlin’ Willows Farm on Nonesuch Road and the owners have said that digging them up would be upsetting, as well as messy, Hoenig said.

An alternative proposed by the department’s soils experts calls for installing a curtain drain – a trench around the burial area lined with crushed rock and a plastic barrier so runoff would be diverted around the burial location instead of leaching through it.

State authorities say they are not worried about botulism contaminating the water table, but are concerned that leachate from the decomposing carcasses might harm water quality.

Linda Beck, who lives on nearby Mountain View Road, said she is worried about water quality. She has already installed a filter system because of high arsenic levels in the groundwater and she doesn’t drink the water, but does use it for cooking. Her husband, Bill Beck, said others also are worried.

“Everybody on this side of the road is concerned about the water table,” said he said. “We need information on where the horses were buried.”

State officials became aware a week and a half ago that almost two dozen horses had died from botulism poisoning. The toxin interferes with the ability of nerves to communicate with muscles, leaving the horses partially paralyzed, unable to swallow or breathe.

Some of the horses recovered from their symptoms, and 40 to 45 horses remain at the farm, Hoenig said.

The state’s investigation into the deaths was sparked by a complaint. A resident called Gorham police, who forwarded the complaint to state authorities, said Town Manager David Cole.

The state welfare agent found no evidence of neglect, and care for the animals meets state standards, Hoenig said. State standards require that horses have waterproof shelter, unlimited access to clean water and enough food to maintain body weight.

He said the state has received at least one other complaint about the farm in the past, but none since January 2010. He said the owners took the corrective action that the state inspectors ordered, but that he did know the nature of that complaint or what inspectors required them to change.

The state is still trying to pinpoint what caused the poisoning, though it has suspects. Horses usually contract botulism from feed and because so many horses were exposed to it at one farm, that is a likely source, Hoenig said.

Inspectors suspect that baleage, partially dried forage in large round bales that is then wrapped in plastic, might be to blame. The practice is common for cow feed because the partially dried grass has more nutrients than fully dried hay and does not require three straight days of dry weather after being cut, as regular hay does.

However, the sealed bales can create the oxygen-free conditions for the botulism bacteria to grow, especially if a dead rodent or other animal is baled with the hay. Cows are less susceptible because their digestive system includes a stomach with four compartments that reduces the impact of impurities. Horses, on the other hand, have very sensitive digestive systems, said Richard Brzozowski, of the University of Maine Cooperative Extension.

Experts recommend that owners who feed baleage to horses make sure the animals are vaccinated against botulism.

Marilyn Goodreau, president of the Maine State Society for the Protection of Animals, which runs a horse rescue farm in Windham, said she will not use the sealed bales of hay.
“You wouldn’t feed that to horses,” she said. “It deteriorates and it breaks down and can get black and dusty and has a lot of bacteria.”

Goodreau would not say whether she received any complaints about the farm, saying such referrals are confidential.

The large-scale death of horses from botulism is almost unheard of in Maine, though not nationally. Experts at the University of Pennsylvania’s National Botulism Reference Laboratory said there have been livestock deaths elsewhere in the country, although botulism death among horses is rare.

“It’s most common in the mid-Atlantic region, but even there is it is a relatively uncommon disease,” said Dr. Amy Johnson, a consultant for the lab and neurology professor at the university.

In one California case in the 1990s, botulism was diagnosed in a dairy herd where more than 400 cows died after they ate feed that had been contaminated by a dead cat. And in Florida, botulism in feed caused the death of more than 120 horses.

The bacteria that causes botulism is common in the soil, but it is usually in its spore form, which is not dangerous, Johnson said. It is only when it is in anaerobic conditions – when there is no oxygen present – that it transforms into its vegetative state and gives off the deadly toxin.

Staff Writer David Hench can be contacted at 791-6327 or at: dhench@pressherald.com