We applaud FDA Commissioner Mark McClellan for implementing new layers of protection against bovine spongiform encephalopathy (BSE). Preventing potentially risky tissue, like meat from down or dead cattle, and specified risk materials from cattle older than 30 months, from entering the human food supply is critical for preventing the human form of mad cow disease.

One of the positive consequences of the recent BSE discovery is a renewed focus on animal feed. Many Americans were surprised to learn that cattle are sometimes fed cow blood and so-called "poultry litter." We hope that the FDA takes its feed ban a step further by banning all mammalian protein, especially specified risk materials, from the entire animal food chain. Short of an inspector in every barn, there is no other way to ensure that feed containing any beef remains does not get fed to cattle.

And if more restrictions on animal feed cost the beef industry a little money, it will only be a fraction of what it would lose if our trading partners continue to spurn American beef.