California BSE Cow Found to be Isolated Case
August 10, 2012

On Tuesday, the U.S. Department of Agriculture (USDA) released its final report on the epidemiological investigation of a dairy cow from California that tested positive for bovine spongiform encephalopathy (BSE) in April 2012. 
In accordance with World Organization for Animal Health guidance, USDA conducted a thorough epidemiological investigation following the BSE detection. This included on-the-ground investigations and records review from the rendering facility, the index farm and associated premises, as well as traceback for progeny and birth cohorts of the index cow. 
The results of this thorough investigation confirmed that at no time was the U.S. food supply or human health at risk, and that the United States' longstanding system of interlocking safeguards against BSE continues to be effective. 
This case was found in an animal that was sampled for the disease at a rendering facility in central California. This animal was never presented for slaughter for human consumption, so at no time presented a risk to the food supply, or to human health in the United States. 
The index animal was a 10 year 7 month-old Holstein cow from a central California dairy. The animal was humanely euthanized after it developed lameness and became recumbent, and was sampled by a renderer contracted to collect samples as part of USDA's ongoing BSE surveillance. Test results confirmed that the index cow was positive for atypical (L-type) BSE. 
The final report can be viewed at