"The inconclusive result does not mean we have found another case of BSE in this country. Inconclusive results are a normal component of screening tests, which are designed to be extremely sensitive so they will detect any sample that could possibly be positive," cautioned Andrea Morgan, associate deputy administrator, Animal and Plant Health Inspection Service.
She did not reveal the location of the questionable samples.
While the Service has taken traceback steps, the lab results won't be ready for four to seven days, Morgan said. However, noting that results such as this one are "not unexpected," Morgan did not exclude the possibility that a subset of animals may in fact turn out to be positive for BSE.
"USDA remains confident in the safety of the U.S. beef supply. Our ban on specified risk materials from the human food chain provides the protection to public health, should another case of BSE ever be detected in the United States," Morgan continued. "Our surveillance program is designed to test as many animals as we can in the populations that are considered to be at high risk for BSE."