Why won't the USDA let Creekstone Farms test for mad cow disease?

In what can only be considered a curious move, the USDA recently went to court to stop Creekstone Farms Premium Beef from testing every single one of their cows for Mad Cow disease. Though there have only been a handful of confirmed cases of the disease in the United States, currently only 1% of slaughtered animals are tested for Mad Cow, which is fatal to humans who eat infected meat.

Why does the USDA care if Creekstone wants to test their animals? According to the article, if Creekstone is allowed to move ahead with testing, they'll have "an advantage" over large meat packing companies who can't or won't carry out the testing themselves, and that false positives may harm the meat industry.

While Mad Cow hasn't become a problem in the U.S. yet, it's clear that if and when it does, the meat packing industry isn't prepared to deal with it. In 2005, a consumer group found over 800 violations at U.S. plants and discovered that nearly half of the plants involved had food safety plans that didn't mention Mad Cow. What do you think? Should Creekstone be allowed to test at will, or do you think it's the USDA's job to protect the industry at all costs?