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About Zilmax

Raising quality, responsible beef sustainably

We support cattle farmers in their commitment to continue finding better ways to provide quality beef for you and your family. Zilmax is an FDA-approved feed supplement that improves cattle's natural ability to convert feed into more lean beef1,4,5 that is flavorful, tender and juicy.2,3

This feed supplement helps cattle farmers raise beef more sustainably. It aids cattle in making the most of what they eat. It is fed for a short period of time during the finishing phase, when cattle become less efficient at metabolizing their feed and typically gain excess fat.

As a result, farmers use fewer natural resources8 while raising more quality beef,1 and that helps keep beef an affordable choice for you and your family.7

History of use

Farmers have been using this feed supplement for more than two decades. It was first approved outside the U.S. in 1995 and approved in the U.S. in 2006. As billions of consumers in developed and developing countries want to increase the amount of protein in their diets, more countries are interested in registering Zilmax for use. To date, in addition to the U.S. and Canada, 14 countries have already reviewed and registered the product for use, and eight other countries are in the process of reviewing information required for registration.

Good for the environment and good for you

As the growing global middle class consumes more beef, overall demand is rising and driving beef prices higher. That's just a matter of supply and demand. This is occurring at a time when U.S. beef cattle numbers are at their lowest point in more than 60 years. By feeding this supplement to cattle, farmers can provide more quality beef,1 increasing supplies – especially during these times of tight supplies. And, greater supplies of beef means farmers are better able to keep beef an affordable choice for you and your family.7

Because Zilmax improves cattle's natural ability to convert their feed into more quality beef,1,4,5 it also means farmers can raise that beef with fewer cattle.9 Fewer cattle = less waste, and less use of land, water and energy.9 This is just one example of how farmers continue to advance the way cattle are raised with less impact on the environment. Research shows that farmers today, compared to their grandfathers, provide 13 percent more total beef from 30 percent fewer animals, and the carbon footprint of beef has been reduced by more than 16 percent.9 Now that's good for the environment and all of us.

Same quality-beef eating experience

Those benefits are accomplished without sacrificing the flavor, tenderness or juiciness of the beef we all love. In the largest grilled steak taste-test study ever, consumers rated beef from cattle fed Zilmax as flavorful, tender and juicy2 – the same consumer acceptability as beef from cattle that were not fed Zilmax (control). The results confirm other studies in which consumers found no difference between USDA Choice or Select quality grade strip steaks from cattle fed Zilmax or control cattle.3

Responsible approach

At Merck Animal Health, we're dedicated to making science-based decisions in everything we do. Before any animal health product is approved for use, it must be proven safe and effective by the FDA through comprehensive and rigorous testing. Merck Animal Health has conducted extensive research with Zilmax, far more than required by the FDA, making Zilmax one of the most researched animal health products.

When questions were raised about Zilmax and animal well-being, our natural response was to investigate thoroughly. Under the guidance of an industry advisory board, a five-step plan was prepared, which included reinforcing checks and balances to ensure proper product use and the commitment to conduct additional research. We also felt it was right to voluntarily suspend sales of Zilmax while we worked through the five-step plan.

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, which can be prevented by proper animal management protocols.29

We believe the results of the research and other outcomes not only answered the questions raised, but also provided new information for continuous industry improvement. It's just one example of our commitment to support farmers with science-based solutions and ongoing research that helps them raise cattle responsibly.

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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.