SAN JOSE, Calif. (MCT) — America’s beef industry and federal agriculture officials spent much of the past week reassuring the public that the nation’s meat supply is safe, after the announcement that a California dairy cow tested positive for mad cow disease.

But even as investigators from the U.S. Department of Agriculture continue to comb through the herd and the records at a Tulare County farm where the animal came from, the fourth case of mad cow disease detected in the U.S. since 2003 is sparking new debate about whether food-safety laws are adequate to protect public health.