The president of Zensho Co., operator of the Sukiya chain of restaurants, voiced opposition Monday to the government's plan to ease blanket testing of cattle for mad cow disease.

"Testing all cows is necessary if (food) safety is the basic premise," Kentaro Ogawa said, distancing himself from many other Japanese fast-food restaurant operators who are in favor of the government plan, which would pave the way for resuming imports of U.S. beef.

These Japanese-style fast-food restaurants serve "gyudon" beef-on-rice bowls.

The proposed method of verifying the age of cattle by such means as the meat color is not enough because meat quality differs widely among certain cows, Ogawa said.

The government plans to exclude beef from cattle slaughtered at 20 months of age or younger from tests for mad cow disease, formally known as bovine spongiform encephalopathy, because it is difficult to determine whether young cows are infected with the brain-wasting disease.

The plan is based on a report by the Food Safety Commission earlier this year suggesting that even if young cattle were excluded from the test, the resultant increase in BSE risk would be extremely low.

Yoshinoya D&C Co., the biggest gyudon restaurant chain, maintains that the safety of beef can be secured if brains and other specified risk materials are removed from cows.

But Ogawa said it would be difficult to use American beef due to concerns about safety and available quantity.

According to earnings reports for fiscal 2004, consolidated sales at Yoshinoya dropped 16.4 percent compared to the previous year. Zensho saw an 11.8 percent rise in its group sales.