WASHINGTON (AP) – Japanese lawmakers told Agriculture Secretary Mike Johanns on Tuesday that a shipment of American beef containing bones prohibited because of the risk of mad cow disease had caused deep suspicion among consumers in Japan.

“It was a very heated discussion,” Takashi Shinohara, member of the opposition Democratic Party, said after meeting with Johanns. “Many, many different consumers distrust the American way of inspection and are very much disappointed.”

Japan suspended imports of U.S. beef on Jan. 20 after finding a veal shipment containing backbone, which Asian countries consider at risk for mad cow disease. The cut, veal hotel rack, is consumed in the United States but not allowed in Japan.

The mistake has endangered millions of dollars in potential sales to Japan, which reopened its market to U.S. beef only weeks ago.

The issue prompted opposition lawmakers to walk out of a session Monday in the Diet, the Japanese parliament.

They were upset that Tokyo failed to inspect U.S. meat plants before resuming trade with the United States, an admission made recently by Agricultural Minister Shoichi Nakagawa.

Johanns said the mistake could have happened even if Japanese inspectors had visited the plant operated by Atlantic Veal & Lamb in Brooklyn, N.Y. He told reporters after the meeting that Japan had conducted a painstaking, thorough review of the safety of American beef.

“There is nothing about this process that was shortchanged,” Johanns said.

The department is still investigating what went wrong with the shipment, he said.

The opposition lawmakers from Japan said that before beef shipments resume, the United States needs to be able to pinpoint the movements of all its cattle. They also called on the U.S. to test for mad cow disease in every cow that is slaughtered.

Department officials have rejected Japanese demands for testing every animal. Johanns noted that mad cow disease is nearly impossible to detect in animals younger than 24 months, which is Japan’s age requirement for beef imported from the United States.

“It is just something that we’ve looked at, we’ve discussed, we’ve debated over and over again, and it’s not justified by science,” Johanns said.

He noted that the department is working on a tracking system. Johanns announced last May that participation by the industry would be mandatory by 2009, but the department has since eased off that goal. Spokeswoman Dore Mobley said Tuesday it will take longer than originally planned and might be voluntary as well.

Commonly referred to as mad cow disease, bovine spongiform encephalopathy, or BSE, is a degenerative nerve disease in cattle that is linked in humans to variant Creutzfeldt-Jakob disease, a rare but fatal illness.

Japan banned American beef after the U.S. discovered its first case of BSE. A second U.S. case was confirmed last June. Japan confirmed its 22nd case on Tuesday.

AP-ES-01-31-06 1733EST