Mad Cow Roulette

Agriculture Department admits: Its testing was never meant to stop a diseased cow from reaching the public, Dr. Ron DeHaven, the department's chief veterinarian. It was meant to reach a statistical level of probability that it could spot one case in a million.

If they've found one infected animal in a million, how many more are out there?

Since 1997, Consumers Union, which publishes Consumer Reports, has sent numerous letters to Agriculture Department officials warning that the American testing was "flawed in both design and execution," and that native brain disease, not necessarily caused by feed imported from Britain in the 1980's, "may be hiding among the 'downer cow' population."

It also warned that studies suggested that some pigs suffered from encephalopathy, particularly dangerous because it is still legal to feed rendered pigs - pig parts boiled, ground and dried into a powder - to cows. In 2001, Public Citizen, a consumer group, issued a report saying that testing for mad cow was "in disarray," with huge differences in testing rates among states.