No word on source of Canada’s BSE

SALEM, Ohio – The incidence of bovine spongiform encephalopathy, or BSE, in Canada remains isolated to one cow, first diagnosed May 18.

So far, other than the original beef cow in Alberta, Canada, all test results have come back negative for BSE, commonly known as mad cow disease.

As of Monday, June 9, quarantines had been removed on nine of the 18 farms involved.

1,500 samples. All cattle from these 18 farms have been killed and more than 1,500 samples have been submitted for laboratory tests. Rapid diagnostic tests from these 18 farms have all been negative.

Canada has also depopulated approximately 1,000 additional animals from nonquarantined farms linked to the investigation. All samples submitted for testing came back negative.

These animals are suspected either of having a genetic connection to the infected cow or having consumed the same feed as the infected cow in 1995-96.

Source unknown. Brian Evans, chief veterinary officer of the Canadian Food Inspection Agency, said it may not be possible to determine “with absolute certainty” the origin of the animal.

The most likely source of infection for a cow is through consumption of contaminated feed.

To date, Canada has also conducted 200 targeted and random feed processing inspections.

The agency has indicated its primary investigation stage has concluded.

Bull scare in U.S. As part of the ongoing investigation, on June 3, Canadian and U.S. officials identified five registered Angus bulls that were herdmates of the infected cow and subsequently imported into the United States.

According to the Canadian Food Inspection Agency, these animals are from the Saskatchewan herd suspected to the birth herd of the infected cow.

All animals in that herd have been depopulated and tested negative for BSE.

Breeding bulls. The breeding bulls were born in 1996 and sold to a Montana farm in April 1997. The rancher was able to provide records of the numbers of bulls that were sold, but wasn’t able to provide specific or individual animal identification.

The farm sold 23 bulls, which officials presume included the five in question, to auction markets in several states from 1997 to 2002. Another bull was slaughtered for personal consumption.

The USDA is working with the rancher, slaughterhouse owners and officials in Montana, Nebraska, Minnesota, Texas, South Dakota and Wyoming to determine the final status of these bulls.

Little risk. “We think it’s highly unlikely that any of these five animals would have been infected with BSE,” said Ron DeHaven, deputy administrator for veterinary services with the USDA’s Animal and Plant Health Inspection Service.

DeHaven added that even though these were breeding bulls, bovine semen scientifically is “not a threat in terms of a means of transmitting the disease.”

No word on ban. U.S. officials were mum on the lifting of the U.S. ban on the import of Canadian beef.

“As long as we have an investigation that is ongoing, it’s simply not prudent for us to consider lifting restrictions at this time,” DeHaven said.

An international panel reviewed the Canadian investigation and was scheduled to present its report earlier this week.

Elsewhere. “It is good news that odd single cases of BSE are being picked up by inspection,” said Andrew Speedy, animal health officer with the Food and Agriculture Organization of the United Nations.

“It demonstrates that active surveillance is picking up the one-in-a-million case.”

Cases of BSE found since 2001 include cases in countries like the Czech Republic (4), Greece (1), Israel (1), Japan (7), Luxembourg (2), Poland (5), Slovakia (11) and Slovenia (3).

In the UK outbreak, mad cow disease peaked in 1992 with 37,000 cases and dropped to 1,144 cases in 2002.

Mad cow disease is a degenerative disease affecting the central nervous system of cattle. The incubation period ranges from two to eight years.

It has never been found in the United States.