The U.S. Agriculture Department said Wednesday its investigation into the first U.S. case of mad cow disease has expanded to Oregon, after linking a cow there to the infected animal in Washington state.
The USDA said a dairy facility near the Washington state border in Boardman, Oregon, was placed under state quarantine after a cow was determined to be in the same herd as the Holstein dairy cow diagnosed with mad cow disease on Dec. 23.
“It is not unusual for an epidemiological investigation to cover multiple states,” the USDA said in a statement.
'Our dairy products remain safe'
State officials reassured consumers that Oregon dairy products were safe despite the finding. “We want to emphasize that our dairy products remain safe for consumers,” Oregon’s Agriculture Department said in a statement.
USDA investigators are still searching for several dozen cattle that were in the same herd as the infected cow when it was born on an Alberta, Canada, dairy farm.
As many as 98 animals were raised together in Canada --which means they may have shared the same source of feed -- and then sent to the United States in two shipments in 2001. The USDA said it has yet to locate 71 of the animals.
Six herds in Washington state have also been quarantined because of links with the infected cow.
The USDA has killed 620 cattle in three quarantined herds as an extra precaution. So far, the animals have tested negative for the disease.