Japan has confirmed its 14th case of mad cow disease.

Officials said Thursday that a four-year-old cow found dead on the northernmost main island of Hokkaido Saturday tested positive for the ailment.

Japan found its first case of mad cow disease in September 2001, and has since tested every cow before it is used for consumption.

Japan also halted imports of U.S. beef in December 2003 after the United States reported its first case of the disease, which is formally known as bovine spongiform encephalopathy.