Tissue samples collected as part of the USDA’s enhanced Bovine Spongiform Encephalopathy (BSE) surveillance program tested inconclusive on an initial screening test. The cow was non-ambulatory when examined by a local veterinarian who euthanized the animal and submitted tissues to a lab at the University of Georgia.
According to a USDA press statement, the department received notification of the inconclusive result Friday evening March 11th. The samples were forwarded to the National Veterinary Services Laboratory (NVSL) and USDA’s Agricultural Research Service (ARS) for immunohistochemistry (IHC) and Western blot testing. The animal was buried on the farm and thus did not enter the human food or animal feed chain.
Results from the Western blot test, released on March 13th, confirm that the animal, a 10 year old beef cow from Alabama, was positive for BSE. The IHC results should be completed by the end of this week, but the Western blot is considered confirmatory. The USDA is now working to locate any birth cohorts and offspring.
A ruminant feed ban was enacted in 1997 to prevent the feeding of ruminant by-products to ruminants, believed to be the most likely route of transmission for the prions which cause BSE. In 2004, the USDA implemented the enhanced surveillance testing program for BSE. Since then, the department has tested more than 640,000 high risk animals and more than 20,000 clinically normal older animals. Only one, a high risk animal, had previously tested positive. The USDA had planned to scale back the testing program in 2007, budgeting to test only 40,000 animals.
Source:
USDA press release No. 0080.06
MeatingPlace.com, Daily News March 14, 2006
BrownfieldAgNews.com, March 13, 2006