Two US dairy farms quarantined after mad cow disease case

Two California dairy farms are under quarantine and a calf ranch is under investigation after the latest U.S. case of mad cow disease was found, but the USDA said the actions were standard procedure and there is no threat to the food supply, reports Reuters.

Also, a calf born to the infected cow was found and tested negative for the disease, the article stated.

Cattle records at the two dairies are being matched to determine if any at-risk cattle are on the farms, said the Agriculture Department.