US mad cow case 'atypical' say investigators
Quarantine lifted on farm of origin, investigation near completion
A California cow diagnosed with mad cow disease in April has been found to have an atypical version, according to laboratories associated with the World Organization for Animal Health and the U.S. Department of Agriculture.
The quarantine has been lifted on the farm where the latest case originated as the case nears completion, said the USDA. Out of several hundred cattle that may have been born at the same time and area as the infected cow, the investigation seeks roughly 10 to 12 animals that may still be alive and have ownership records that allow tracing. The rest of the birth cohort are no longer alive or otherwise ruled out.