The 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. From the executive summary:
The index animal was a 10 year 7 month-old Holstein cow from a central California dairy. The animal was sampled by a renderer contracted to collect samples as part of USDA’s ongoing BSE surveillance. Results from immunohistochemistry and Western blot tests at USDA’s National Veterinary Services Laboratories (NVSL) confirmed the animal positive for atypical BSE. Two offspring of the index animal were designated as at-risk cattle. One was traced out-of-State and depopulated with “not detected” BSE test results. The other offspring was stillborn. The carcass of the index animal (along with approximately 90 other carcasses being held at the renderer’s transfer station), were disposed of in a landfill in accordance with all Federal, State and local regulations. The carcass of the index animal did not enter the human or animal food chain.