MABTON, WA - DECEMBER 27 : A no trespassing sign is seen as cows eat at the Sunny Dene Ranch December 27, 2003, in Mabton, Washington. The farm has been quarantined by the U.S.D.A after it determined that a cow that came from the farm has been infected with mad cow disease. (Photo by Justin Sullivan/Getty Images)
A case of mad cow disease was discovered in Central California, although the cow was not slaughtered for consumption and its milk does not transmit the disease, an official with the U.S. Department of Agriculture said Tuesday.
The carcass of the dairy cow is being held at a rendering facility in California and will be destroyed, USDA Chief Veterinary Officer John Clifford said in a statement.
The discovery marks the nation's fourth confirmed case of mad cow disease, also known as bovine spongiform encephalopathy.
"USDA remains confident in the health of the national herd and the safety of beef and dairy products. As the epidemiological investigation progresses, USDA will continue to communicate findings in a timely and transparent manner," Clifford said.
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