SUMMIT, NJ – Merck Animal Health announced it will, in conjunction with independent experts, conduct a scientific audit that will monitor the process of feeding Zilmax (an FDA-approved feed supplement to improve cattle’s ability to convert feed into more lean beef) to cattle, and will follow identified cattle from the feedyard to the packing plant to determine potential causes of recently reported lameness and other mobility issues during feeding, transportation, offloading and staging at the processing facility. It plans to conduct a thorough review of potential compounding factors, such as nutrition, transportation and receiving facilities.

In response to recent questions about Zilmax, Merck Animal Health released on Aug. 13 its Five-Step Approach to Ensuring Responsible Beef to help inform its customers and interested groups on the safety and effectiveness of this supplement (read 
“Merck Animal Health sets course to vindicate Zilmax”in the Aug. 13 edition of for more details).

This morning the company announced it was temporarily suspending sales of Zilmax in the United States and Canada to provide sufficient time to establish valid study protocols, identify feeders and packers to participate in the audit, and create a third-party team to oversee this process and validate its results.

"We remain confident in the safety of the product, based on our own extensive research and that of regulators and academic institutions, and are committed to the well-being of the animals that receive it," says KJ Varma, BVSc, Ph.D., Diplomate ACVCP, senior vice president Global R&D, Merck Animal Health. "This important step demonstrates our commitment to providing our industry partners with data that will reaffirm confidence in Zilmax. We sincerely regret that this situation creates business challenges for our customers; but it is critical to ensure this process is conducted appropriately and with rigorous scientific measures.”

The company is also speeding up developing its Merck Animal Health Advisory Board, which will bring together industry experts, producers, academics and company leadership to promote an open dialogue on animal well-being and help shape and strengthen the company's animal health and well-being program in the future.

Zilmax sales in the US and Canada were $159 million in 2012.