Referring to a recent incident in Texas, in which a cow with symptoms consistent with mad cow disease was not tested, the Iowan Democrat said the case "calls into question the effectiveness and reliability of USDA's current and proposed surveillance system."
The USDA has proposed testing more than 200,000 cows -- or 10 times its current rate -- in an expanded program scheduled to begin June 1. But Harkin writes that given the realities of the cattle industry, it is "quite doubtful" the USDA will be able to test that many cows, particularly considering it had difficulty finding just 20,000 last year.
Harkin also questioned the validity of the statistics the USDA used to arrive at the conclusion it would be able to detect mad cow if it was prevalent at the low rate of 1 case per 10 million cows.
He urged Veneman to address those alleged shortcomings.