Canada’s Food Inspection Agency said the latest case of bovine spongiform encephalopathy (BSE) surfaced in a six-year-old dairy cow in the Fraser Valley on the Pacific coast, during a national surveillance program.
Health officials said despite the findings, beef for human consumption remains safe because the BSE-infected parts of cattle do not enter the food chain.
“This finding does not affect the safety of Canadian beef,” Canadian health authorities in a statement.
“No part of this animal entered the human food or animal feed systems.”
Mad cow disease has been connected to the fatal brain-wasting disease in humans called variant Creutzfeldt-Jakob disease.
Second case this year
The discovery is the second this year and fifth overall in Canada, with the earlier cases provoking US and Japanese embargoes on imports of Canadian cows and beef, costing Canada’s cattle farmers billions of dollars.
The US resumed imports of Canadian cattle under 30 months and of young live cattle for slaughter this year.
In Washington, Agriculture Secretary Mike Johanns said he does not expect the finding to result in any changes in US-Canada beef and cattle trade.
“Based on the information currently available, I do not anticipate a change in the status of our trade,” Mr Johanns said in a statement, adding that Canada had invited US participation in the investigation.
“Information gathered through this investigation will help us to determine what, if any, impact this should have on our beef and live cattle trade with Canada,” said Mr Johanns.
Canadian authorities said they would conduct a thorough investigation into the source of the new infection, which comes after controls were tightened on cattle feed, to which earlier cases were sourced.
Since the discovery of Canada’s first BSE case in 2003, around 100,000 animals have been tested in a surveillance program, which targets the animals most at risk.
Experts say more than 150 people, mostly in Britain, have died from vCJD as a result of eating BSE-infected beef.