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Animal Well-being

Like you, we care

At Merck Animal Health, caring for the health and well-being of animals is more than just a business, it’s who we are. We believe in using science to find ways to continually improve the health, well-being and natural growth potential of animals.

Extensive research finds Zilmax is safe for cattle

Before Zilmax was approved, we worked with university and industry experts who conducted research on many aspects of the product to ensure its safety and effectiveness. The research confirmed Zilmax is safe and effective for cattle and has no negative impact on their well-being, when used according to label directions along with good animal care practices.1,10-20 Even when our product is approved and in use by our customers, we conduct ongoing research in search of continuous improvement.

Doing the right thing

Our product is safe and the science supports it. In August 2013, when questions were raised regarding Zilmax and animal well-being, we listened. Sometimes you have to step back and reconfirm the safety in today’s environment – for the cattle, our customers and the industry. Under the guidance of an industry advisory board, a five-step plan was prepared to address the questions. This plan included reinforcing checks and balances to ensure proper product use and the commitment to conduct additional research. We also felt it was the right thing to voluntarily suspend sales of Zilmax while we work through the five-step plan.

During this time, we’ve made a lot of progress

  • Mobility surveillance data collected by third-party trained evaluators who observed and scored the mobility of more than 60,000 head of cattle in 33 feedyards and seven plants.
  • Independent research teams from USDA and seven universities conducted comprehensive studies to evaluate cattle fed Zilmax against numerous parameters of cattle safety and well-being, including animal mobility, behavior, stress and physiological indicators.
  • FDA approval of a new targeted lower dose.
  • Creation of feedyard training, certification and best management practices.

Findings: Zilmax has no impact on animal well-being

When used according to label directions along with good animal care practices, the results from the observations and additional studies all reaffirm Zilmax's safety and conclude that it has no negative impact on the well-being of cattle.1,10-20

Researchers also looked at a specific animal well-being question raised by the industry. The experts concluded it was a multi-factorial incident known as Fatigued Cattle Syndrome (FCS), which can be prevented by proper animal management protocols.29

Merck Animal Health supports efforts to further identify factors involved in FCS, and protocols that result in improved animal well-being.

If you want more information about the animal well-being research, please contact us at beef@merck.com.

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Answers About Zilmax®

Zilmax has a withdrawal period 3 days prior to slaughter. Not for use in animals intended for breeding. Do not allow horses or other equines access to feed containing zilpaterol. Do not use in veal calves. Not to be fed to cattle in excess of 90 mg zilpaterol/head/day in complete feed. If pen consumption of complete feed exceeds 26.5 lb/head/day (90% dry matter basis), zilpaterol should not be fed in complete feed.

For complete safety information, please refer to the product label.