The US Agriculture Department said today that DNA test results showed with a "high degree of certainty" that a dairy cow in Washington state infected with mad cow disease was imported from Canada.
"We now have DNA evidence that allows us to verify with a high degree of certainty" the Washington state dairy cow with mad cow disease originated from a dairy farm in Alberta, Canada, said USDA Chief Veterinarian Ron DeHaven.
The USDA has been investigating the nation's first case of mad cow disease, discovered on Dec. 23 in a Holstein dairy cow in Washington state.