A 68-month-old diary cow on a farm in northern Japan's Hokkaido was confirmed to have contracted mad cow disease, the Japanese Ministry of Health, Labor and Welfare announced Wednesday.

This is Japan's 23rd case of mad cow disease, or formally known as bovine spongiform encephalopathy (BSE).

According to the ministry's statement, the female Holstein cow, which was raised in Nakagawa, Hokkaido prefecture, was suspected to have caught the disease in a preliminary test on Monday. Its sample was later sent for re-examination and the results were also positive.

Japan discovered its first mad cow case in September 2001. The government later started introducing measures to screen every cow slaughtered for consumption.

Japan imposed a ban on U.S. beef in December 2003 after the mad cow disease was found in a U.S. herd. The ban, which was lifted in December 2005, has been re-imposed a month later when a U.S. beef shipment was found to contain risky body part.

Source: Xinhua