USDA examining possible new mad cow case

Food & Drink Weekly, August 1, 2005

USDA is conducting more detailed testing at the National Veterinary Services Laboratories in Ames, Iowa--in consultation with experts from the international reference laboratory in Weybridge, England--on a tissue sample that could reveal another case of mad cow disease in the United States. In making the announcement, USDA chief veterinarian John Clifford said, "It is important to note that this animal poses no threat to our food supply because it did not enter the human food or animal feed chains."

The original sample was submitted to USDA by a private veterinarian who had taken it from a cow that was at least 12 years of age and experienced complications during calving. The veterinarian treated the sample with a preservative, which readies it for testing using the immunohistochemistry test, an internationally recognized confirmatory test for mad cow disease. However, because the sample was treated with the preservative, neither the rapid screening test nor the Western blot confirmatory test can now be used.

Clifford noted that the sample was taken in April, at which time the protocols allowed for a preservative to be used (protocols changed in June 2005). "The sample was not submitted to USDA until last week, because the veterinarian set aside the sample after preserving it and simply forgot to send it in," said Clifford.

The American Meat Institute (AMI) said the latest BSE-related incident should not raise concerns among consumers or trading partners because beef is safe from BSE. "The beef we eat, like steaks, roasts and ground beef, is safe," said AMI Foundation President James H. Hodges. "These products have never been associated with a BSE-related human illness. Consumption of certain cattle parts that could harbor the BSE agent if the animal is infected--primarily the brain and spinal cord--has been identified as a possible cause of human illness."