April 10, 2007

USDA says Canada's BSE-positive animal cohort exported to the US
 

One of the birth cohorts of a Canadian bull diagnosed with bovine spongiform encephalopathy (BSE) in January was shipped to the United States in 2002, according to USDA's Animal and Plant Health Inspection Service (APHIS).

The animal, a heifer, was traced to have been sent and slaughtered in Nebraska. APHIS spokeswoman Andrea McNally said the animal presented a negligible risk since scientific data indicate that two BSE-positive animals rarely originate from the same herd.

APHIS official Karen Eggerg said data on cohorts is based on "years of observation" rather than clinical studies, and indicated that one theory why two animals from the same herd are rarely BSE-positive is that prions, the misfolded proteins associated with BSE, generally are clumped together as a result of their sticky nature, and therefore aren't evenly distributed in feed.

After discovering the infected bull, a 79-month-old animal from Alberta, the Canadian Food Inspection Agency focused on cattle born in the same herd within 12 months. The bull became emaciated last winter and subsequently was earmarked for Canada's National BSE Surveillance Program.