U.S. Officials Confiscate Sheep Over Fears of Mad Cow Disease

Federal officials on Wednesday seized a Vermont farmer’s flock of sheep over suspicions that some of the animals may be infected with mad cow disease and could pose a threat to livestock nationwide.

It was the first time that the U.S. government has confiscated livestock as a precaution against mad cow disease. About two dozen federal agents converged on a farm in Greensboro, Vt., at dawn to load 233 sheep and lambs onto trailers. Security agents will escort the animals to a lab in Ames, Iowa, where they will be killed and tested.

The U.S. Department of Agriculture plans to seize a second flock of 140 sheep in East Warren, Vt., within the next few weeks.

It will take at least two years--and possibly much longer--before pathologists can determine for sure whether the animals harbor mad cow disease or a related illness, scrapie, that is relatively common in sheep and cannot be transmitted to humans.

Given the uncertain science, the flocks’ owners have bitterly protested the seizure as premature.

But USDA veterinarian Linda Detwiler insisted that the agency “had no choice but to take decisive action. . . . We needed to take those sheep.”

Mad cow disease, or bovine spongiform encephalopathy, has never been detected in the United States. Yet it has devastated Europe, spreading from Britain to France, Italy, Germany and beyond. Nearly 100 people have died of a human version believed to be transmitted through tainted meat products.

Even if the Vermont sheep do have mad cow disease, the chances of them infecting humans or other livestock are extremely low.

About 50 lambs from the two suspect flocks were sold to local residents for meat several years ago. And cheese made from the ewes’ milk continues to be marketed in Vermont and some neighboring states. But mad cow disease is not known to spread to humans through milk products, or through the cuts of meat that commonly are eaten.

Instead, the disease seems to concentrate in brain and spinal tissue. So the most likely scenario for the Vermont sheep to infect the food chain would be if they were slaughtered, ground up and fed to other livestock. Federal law bans this practice. And the Vermont sheep have been under quarantine since 1998, their every movement monitored by federal inspectors.

Given all those controls, “the risks [the sheep pose] to both animal and human health are very small,” said George Gray, who has studied mad cow disease as director of Harvard University’s center for risk assessment. Nonetheless, he acknowledged, “you can construct a chain of possibles” leading to widespread contamination.

“It’s impossible to say never,” he said. “It’s impossible to say it couldn’t happen.”

And the longer the Vermont sheep grazed their pastures, the more nervous USDA officials got, Detwiler said. “It just increases your chances of something getting away, the longer [the animals] are out there.”

From the owners’ perspective, there is nothing to “get away.”

They are convinced that their animals are healthy--or at worst have scrapie, which crops up in several dozen sheep across the United States each year.

Scrapie shares certain characteristics with mad cow disease. Both illnesses can incubate for years before attacking an animal’s central nervous system. Both show up with the same awful symptoms: animals slipping, falling, scraping against fences and eventually dying--their brains having turned spongy. But scrapie has been around in sheep for 250 years and has never, as far as scientists can tell, jumped the species barrier to infect humans. Mad cow disease has, with devastating results.

The USDA maintains that the Vermont sheep, which were imported from Europe in 1996, could have been exposed to feed tainted with mad cow disease before they came to the U.S. There has never been a documented case of a farm sheep coming down with the disease. But scientists have proved in the lab that it is possible.

So in 1998, the USDA began testing selected sheep from the Vermont flocks. In July of last year, the government found that four sheep had some form of spongy brain disease never before seen in the United States. But the only way to tell whether that disease is scrapie or mad cow is to inject contaminated brain tissue into mice, wait two or three years for them to get sick and then try to identify the disease more precisely. It can take more than one generation of mouse testing--in other words, four to six years or more--to get a conclusive result.

European scientists so far have tested nine sheep suspected of harboring mad cow; all have turned out instead to have some form of scrapie. Tests still are being run on an additional 200 sheep, most of them from the United Kingdom.

Insisting that the link between sheep and mad cow disease is highly speculative at best, the owners of the Vermont flocks have waged a ferocious legal battle to save their animals from destruction.

The U.S. Court of Appeals had scheduled a hearing on their case for April 10. Yet the court also refused to block the USDA from seizing the sheep in the meantime. Detwiler said the confiscation was so urgent that the agency did not want to wait two weeks for the hearing.

“That leaves a bad taste in your mouth,” said Thomas Amidon, the attorney representing Houghton Freeman, who owns the flock seized Wednesday. “It just appears this was a rush to judgment.”

The USDA has promised to pay the owners of the sheep fair market value, but Amidon said an exact price has not yet been determined.

Although the confiscation of Freeman’s sheep went smoothly, friends of the second flock’s owners plan a noisy protest when federal agents come knocking at the farm in East Warren. “We’re all absolutely stunned that our government could be so horrible,” said neighbor Edie Connellee. Added protester Roger Hussey: “They are taking these sheep on the basis of a theoretical risk.”

A theoretical risk, however, is risk enough for many when it comes to mad cow disease.

The Vermont Farm Bureau supported the flock’s destruction. So did the state’s congressional delegation and the American Sheep Industry Assn.

“The impact could be so severe if [mad cow] disease were to come into this country that it seems the action is worth taking--even if the science is not completely sure,” said David Major, a sheep farmer in Putney, Vt. “It’s the old theory: An ounce of prevention is worth a pound of cure.”