Canada establishes birthplace of its lone mad cow

WINNIPEG, Manitoba - Genetic tests have confirmed that a single mad cow, responsible for international trade bans that crippled Canada's beef industry, was born in Canada, a veterinary official said on Tuesday.

Until now, officials were "90 per cent sure" that the cow, found positive for mad cow disease in May, was born on a farm in the Prairie province of Saskatchewan, said George Luterbach, a veterinarian with the Canadian Food Inspection Agency.

"We were able to cross reference and find the sire -- the father -- and the mother to that animal on a Saskatchewan farm," Luterbach told Reuters.

The confirmation does not add any information to the theories of how the cow became infected with mad cow disease, Luterbach said.

But it confirmed the cow was born in 1997 just before a North American ban on including protein made from cattle and other ruminants in cattle feed, he said -- a practice that scientists believe can spread the disease when material from infected animals is included in the mix.

"It (the result) does reaffirm that the animal was born prior to the ban and therefore very legitimately could have been exposed to meat and bone meal as part of its feed formulation," Luterbach said, adding that young calves are thought to be most susceptible to the disease.

Luterbach noted the cow spent time on two other farms before it ended up in the Northern Alberta herd where it spent its last days, meaning experts can't say conclusively where it ate contaminated feed.

Officials confirmed Canada's first case of mad cow disease on May 20, prompting the United States, Mexico, Japan and other key importers to ban Canadian beef.

The United States and Mexico have partially lifted their bans to allow imports of some boneless cuts of Canadian beef from young animals.

But Canada's export-dependent industry has struggled with a shortage of slaughter space and a backlog of livestock, particularly older cows and bulls.

Investigators struggled to pinpoint the cow's precise birthplace because of incomplete records, but established that it could have spent time on 11 different farms in the cattle heartland of Western Canada.

All possible herdmates of the cow on those farms were destroyed and tested negative for mad cow disease.

Initial DNA testing provided inconclusive results, Luterbach said. But more recent tests compared a "better" sample from the diseased cow's brain to DNA samples from the cattle destroyed during the investigation, he said.

"I think (this result) validated that our response was appropriate and that we were accurate in the directions we took," Luterbach said. "I guess it ruled out that we have somehow missed the mark."

When investigators wrapped up the main part of their search in early July, they said there was a small chance the cow had come from the United States.

But this new finding rules out that possibility, Luterbach said.

- REUTERS