December 28, 2003, Pg. A01

Sick Cow Probably Imported;
U.S. Announces Breakthrough That Canada Disputes

By Shankar Vedantam and Blaine Harden

An ear tag on a slaughtered Washington state Holstein cow found to be infected with mad cow disease shows the animal came from Alberta, Canada, where another case of mad cow disease was discovered in May, government officials said yesterday.

The breakthrough, which a Canadian official disputed, could turn what was thought to be the first case of the disease in the United States into an investigation about the second case in North America -- opening a raft of questions about where else the infection might spread.

The Holstein was part of a herd of 74 animals that was imported in August 2001, and importation records show the herd was headed to a Mattawa, Wash., dairy facility, officials said. Two months later, records show the infected Holstein was sent to the Sunny Dene Ranch in Mabton, Wash., from which it was sent to slaughter on Dec. 9. It is not known where the other animals were sent or whether any of them are infected.

"Most of them are likely still alive," said W. Ron DeHaven, deputy administrator and chief veterinary officer at the U.S. Department of Agriculture. "Because records on dairy cattle are typically very good, we feel confident we will be able to determine the whereabouts of most if not all these animals in the next several days."

Tracking the Holstein's roots to Canada will force investigators to confront the possible links between the Washington state Holstein and the Alberta case of mad cow disease. Officials do not yet know whether the animals lived on the same farm or ate the same contaminated feed, which is how the disease most often is transmitted. As a result, they cannot answer the most pressing questions: Which other animals ate that feed, and where are they now?

The shipment of cows from Alberta stayed at Behling Dairy Management, a dairy and specialized feedlot for young dairy cows in transit. It is in the small town of Mattawa, near the Columbia River in central Washington and about 50 miles north of the Sunny Dene Ranch, where the cows were later sent.

The Mattawa dairy's owner, Jeffrey Behling, said the Canadian cows arrived in the fall of 2001, at a time when large numbers of dairy cattle were being imported from western Canada into Washington for the rapidly growing dairy farms.

"We didn't buy or sell these animals," Behling said. "We took care of them for the owners."

Although Behling said he did not know exactly how long the animals had stayed at his facility, it was probably between a few days and several weeks.

"The animals are often on a truck for 20 or 30 hours," he said. "We would unload them, give them a dry place to lie down, give them feed and water, and we would milk them."

He said that if the Canadian cows stayed at his place for more than a couple of days, they would have been "worked into the dairy operation. We would give them hay, corn, canola meal and cottonseed."

Behling said most of the cows were at least 2 years old and were "regular milking cows." He said they arrived in the middle of a four-year period, from 1999 to 2002, during which many hundreds of cows from Canada were brought into dairy farms in the Yakima Valley.

"After 2002, we have pretty much filled the market," he said.

Canadian authorities found a maze of connections during their investigation into the Alberta case. The animal changed hands frequently. Without knowing the exact source of contaminated feed, investigators had no way to know where else the disease might spread. The discovery of the infected Holstein in Washington state offers a clue -- and a warning: The industrialization of farming, the vast number of cattle on the move across borders, and the scale of dairy, feeding and slaughter operations means that a local problem can spread widely.

Serious discrepancies still dog the investigation: The tag number from the infected Holstein matched Canadian export records, but those records also show the animal was born in April 1997; U.S. farm records had indicated the Holstein was born around 1999. Even more troubling, Canadian records show the cow had two calves before it was shipped across the border; U.S. records show the Holstein was a heifer, an animal that had not yet borne calves.

Brian Evans, the chief veterinary officer with the Canadian Food Inspection Agency, said yesterday that officials were trying to track down the two calves the Holstein is recorded to have given birth to in Canada. If those can be matched with DNA from tissue samples taken from the Holstein before it was slaughtered -- or from two living calves that it bore at Mabton -- Evans said, investigators would have a way "to make sure we are talking about the same animal."

But he added that it is premature to conclude that the diseased cow was Canadian. "As yet, there is no definitive evidence that the BSE-infected cow originated in Canada," he said at a news conference.

DeHaven said the DNA testing may take a week. Further complicating the sleuthing operation, Canadian records do not show the Holstein was born in Alberta. Investigators believe the Holstein was infected shortly after she was born, and need to find the birth herd to determine which other animals might have become infected. The birth herd of the Canadian cow with mad cow disease in May was eventually traced to Saskatchewan.

"What we have is a match to an ear tag that was recovered from the animal at slaughter and records in Canada with that same ear tag number," DeHaven said. "That would suggest the animal came to the U.S. from this herd in Alberta, Canada, but we have not been able to absolutely determine that the herd in Canada was the birth herd."

Experts believe that only a minority of cattle that eat infected feed will become sick. But David Ropeik, director of Risk Communication at the Harvard Center for Risk Analysis, which has studied the potential impact of mad cow disease in the United States, said it is difficult to quantify the exact risk to an individual animal.

Canada instituted a ban in 1997 to keep cattle brain and spinal tissue from being fed to healthy cattle. The same year, the United States also banned the practice, which is believed to be the way that misshapen proteins called prions cause bovine spongiform encephalopathy, or mad cow disease. The animal disease is associated with a fatal brain-wasting disorder in humans called variant Creutzfeld-Jakob disease, and gives the brain a spongelike appearance. There is no cure, and about 154 people have died from the disease, mostly in Britain.

Government officials insist that the nation's food supply is safe. They say that the feed ban on cattle brain and spinal tissue keeps prions out of the human and animal food supply. Still, out of "an abundance of caution" regulators recalled all the meat that passed through a Moses Lake slaughterhouse on the same day as the infected Holstein. Two meat processors have asked grocery stores to pull the material from shelves, but some customers in Oregon and Washington have called stores to say they have already consumed the beef.

In the past few days, DeHaven described the search for the infected Holstein's antecedents as "a spiderweb" of possibilities. The breakthrough came at midnight Friday, when Canadian authorities called him to report that border records showed that 74 dairy cattle from a herd in Alberta were shipped into the United States at Eastport, Idaho, which borders the Canadian province of British Columbia.

One of the cows had a tag number matching that of the infected Holstein. The herd was shipped to a dairy finishing facility in Mattawa, Wash., which prepares pregnant cows for sale. Two months later, in October 2001, the Holstein was sold to the Sunny Dene Ranch in Mabton, Wash. The Holstein gave birth to what farm records show was its first calf, which soon died. A second calf, now a yearling heifer, is one of 4,000 cattle placed under quarantine at Sunny Dene Ranch. A third bull calf born recently is at a feeding operation in Sunnyside, Wash., where 400 young animals also have been placed under quarantine.

DeHaven said that scientists at the USDA are studying whether it is necessary to kill these animals to keep the disease from spreading.

Large numbers of dairy and beef cattle were exported in the 1990s by Canada to the United States -- especially the Northwest. Because of overproduction, said Arthur C. Linton, a cattle geneticist at Washington State University in Prosser, Wash., the animals could be exported at a very competitive cost.

Following the discovery of the Alberta case of mad cow disease this May, the United States suspended beef and cattle imports from Canada. Beef products, meat products and cuts of meat are now being allowed in, DeHaven said. On Wednesday, he said the USDA recently had proposed a rule that would allow importation of live animals from Canada. The National Beef Cattlemen's Association yesterday called for an "indefinite extension" of the comment period on the proposal.

Staff researcher Madonna Lebling contributed to this report. Harden reported from Seattle.

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