USDA Orders More BSE Testing of Cow

WASHINGTON - Jun 11/05 - SNS -- The USDA has ordered additional testing of a beef cow for Bovine Spongiform Encephalopathy (BSE) because tests done in the United States came back with an inconclusive result.

Samples of the cow will be submitted to an internationally recognized laboratory in Weybridge, England for independent confirmation of the status of the animal. The Agriculture Department will also conduct further tests.

The USDA's Dr. John Clifford said earlier since the USDA started testing animals for BSE, three animals tested inconclusive and were subsequently subjected to immunohistochemistry, or IHC, testing. The IHC is an internationally recognized confirmatory test for BSE. All three inconclusive samples tested negative using IHC.

However, this week the USDA's Office of the Inspector General (OIG) recommended samples from those cattle "be subjected to a second internationally recognized confirmatory test, the OIE-recognized SAF immunoblot test, often referred to as the Western blot test. We received final results a short time ago. Of the three samples, two were negative, but the third came back reactive.

"Because of the conflicting results on the IHC and Western blot tests, a sample from this animal will be sent to the OIE-recognized reference laboratory for BSE in Weybridge, England. USDA will also be conducting further testing, which will take several days to complete."

Clifford stressed, "Regardless of the outcome, it is critical to note that USDA has in place a sound system of interlocking safeguards to protect human and animal health from BSE-including, most significantly, a ban on specified risk materials from the human food supply. In the case of this animal, it was a non-ambulatory (downer) animal and as such was banned from the food supply. It was processed at a facility that handles only animals unsuitable for human consumption, and the carcass was incinerated.

"USDA's enhanced surveillance program is designed to provide information about the level of prevalence of BSE in the United States. Since the inception of this program, we have fully anticipated the possibility that additional cases of BSE would be found. And, in fact, we are extremely gratified that to date, more than 375,000 animals have been tested for the disease and, with the exception of the conflicting results we have received on this one animal, all have ultimately proven to be negative for the disease."