Japan will need to provide sound scientific evidence if it plans to have stricter regulations to combat mad cow disease than the World Organization for Animal Health (OIE), according to an honorary adviser to the international body.

Proposed changes to the OIE's international standards for fighting bovine spongiform encephalopathy, now being discussed in Paris, would allow countries to trade meat more freely as long as risky parts, including the brain, are excluded and other steps are taken to minimize infection.

"Even if Japan alone opposes the draft, it will be an international standard as long as most countries agree to it," Yoshihiro Ozawa said in a recent interview. "If Japan advocates safety measures that are stricter than global standards, a scientifically sound reason is necessary."

Earlier this month, Japan's independent Food Safety Commission proposed the government ease its blanket testing of cows for mad cow disease. The commission endorsed a recommendation that cattle slaughtered at 20 months of age or younger be excluded from tests for the disease.

The OIE draft includes a simplified system to rate countries based on their abilities to check outbreaks and remove risky animal parts.

"Regulations on BSE will be drastically changed, so it won't be easy for every country to fully understand the draft and agree to it," Ozawa said.

He said the general direction of the draft will probably be approved during the meeting, but if an agreement is not reached, specialists will review the details sometime around July.

Ozawa said the OIE sets its standards on diagnosing methods and vaccines to prevent the spread of animal diseases, including BSE, bird flu and foot-and-mouth disease, by collecting information from countries around the world.