After a series of conflicting test results in the U.S., last week a sample of brain matter from a cow suspected of having been infected with bovine spongiform encephalopathy (BSE), or mad cow disease, was delivered to a British government-run veterinary laboratory in Weybridge, Surrey.
The U.S. cattle industry, and in particular, U.S. agriculture secretary Mike Johanns, now wait with bated breath for the results which will decide one way or another whether the sample from the animal shows conclusively that it suffered from the fatal brain-wasting disease.
Japan, a key importer of U.S. beef, fortunately for the U.S., appears relaxed about the possibility of a positive test result. Japan banned U.S. beef imports in December 2003 after the first and only case of BSE in the U.S. was discovered.
The agricultural counselor at the Japanese embassy in Washington, Shin Yokoyama, said his country was not concerned because the animal in question was old and had not entered the U.S. food chain. He says Japan would not be concerned if the test proved positive.
Mr Johanns has repeatedly confirmed that the animal concerned was destroyed before reaching a slaughterhouse and never posed a risk to human health. It was also born before a ban on using animal feed that uses ingredients from other ruminants was in force in 1997.
The assurances however, are not alleviating the concerns of cattle markets, ranchers and consumer groups who remain edgy, as questions about the effectiveness of the United States Department of Agriculture's (USDA) testing regime are raised.
The ordering of a third type of test by the Inspector-General of USDA called the "western blot" on the sample, after two initial types of tests threw up conflicting results, has sparked the concerns.
The U.S. normally relies on initial "rapid tests" and a second test called immunohistochemistry (IHC) that meets internationally accepted standards for BSE testing.
The USDA has come under fire in recent months for resisting pressure to use the western blot test commonly used in Europe and Japan, as according to the Consumers' Union, an independent organization based in New York, the western blot is 1,000 times more accurate than the IHC.
Leo McDonnell, president of R-Calf, which represents thousands of cattle producers, says U.S. cattle producers had understood the issue was settled more than seven months ago because the USDA told the public the BSE tests it used were 'gold standard'.
Jim McAdams, president of the National Cattlemen's Beef Association, which represents 250,000 out of the 800,000 U.S. cattle ranchers, has expressed "very deep concerns" that the USDA has undermined its own mad cow testing program by retesting the suspect animal. He says that action has created great anxiety within the industry.