WASHINGTON – A new certification is available to beef or pork suppliers that want to market their products as never fed beta agonists and free of beta-agonist residues, the US Department of Agriculture's Agricultural Marketing Service reported.

The program is open to livestock, beef and pork producers that submit marketing programs to the Livestock, Poultry and Seed (LPS) Program for verification and monitoring, according to AMS. The agency said companies must submit documentation that meets requirements under the Process Verified and Quality System Assessment programs, among other requirements.

Zilpaterol came under intense scrutiny after Springdale, Ark.-based Tyson Foods Inc. announced it would stop buying cattle fed zilpaterol on concerns the feed additive was causing lameness in cattle and negatively impacting beef quality. In August, Merck Animal Health, which manufactured Zilmax (zilpaterol hydrochloride), stopped sales of the product in the United States and Canada. The company said it would conduct a scientific audit to monitor the process of feeding Zilmax to cattle.