Through a commitment to cattle, its customers and the industry, Merck Animal Health announced the Food and Drug Administration approved of a second feeding method for the beta agonist Zilmax and has made significant progress on its Five-Step Plan to Ensuring Responsible Beef.

The newly approved label allows for a new method of feeding Zilmax to cattle through a single feeding instead of the previously approved continuous feeding method. Merck Technical Services Nutritionist David Yates, PhD, says it provides a targeted, lower dose of Zilmax for the cattle. Called “component feeding,” Yates says it will be the first in-class component feeding approval for a beta agonist.

Currently, the label prescribes feeding Zilmax at 6.8 grams per ton in a 90 percent dry ration for the last 20 days on feed to provide 60 to 90 milligrams Zilmax per head per day. Yates says the continuous feeding method could result in cattle eating more than 90 mg’s due to the increases in slaughter weights of cattle and the resultant greater consumption of these cattle.   The newly-approved component feeding label, however, will allow for a set amount of feed to contain a set amount of product.

“It’s a different way to feed but it’s a single feeding so from a feedlot perspective, it’s very, very efficient,” says Yates. “One feeding with that product and then you don’t feed that product the rest of the day.”

Yates says Merck worked proactively with FDA on the continuous feeding label to prevent animals from consuming more than 90 mg Zilmax per day, which he said relates to a pen consumption of 26.5 pounds. If a pen of cattle is consuming greater than 26.5 pounds prior to initiation of the feeding or is expected to have that level of intake during the last 23 days on feed, Yates says the pen would not qualify to be fed Zilmax under the continuous feeding label.

“Cattle, based on size and consumption, may or may not qualify for both. All cattle will be able to be fed with the component label but these larger cattle with larger intakes cannot use continuous feeding method,” explains Yates. “Whether you’re feeding five pounds in a single feeding or 10 pounds, you’ve put the right amount in the feed so they get 60 mg per head per day in that size of feeding.”

Continuous feeding of Zilmax consistently resulted in an addition 33 pounds of carcass weight on steers. Yates says growth levels under the component feeding label will “be in the same ballpark but may be a little less.”

In addition to the label changes, Yates says one of the first steps in the five-step plan was for the Merck’s advisory board, consisting of scientists, veterinarians, nutritionists, large and small cattle feeders, packer and other industry representatives, to review, assess and redraft a certification program for feedyards to feed the product. Yates says Merck accepted all of the advisory board’s recommendations and “added additional rigor” to the certification program. For example, feedyard personnel including the feedyard veterinarian and nutritionist will be required to participate in and pass an annual training and recertification program.

Additionally, part of the certification process will include abiding to more than 15 specific Standard Operating Procedures (SOPs) which have been developed for practices including feed milling, sequencing, feed delivery, pen management, withdrawal management and more. Yates says the SOPs were designed to help ensure the product is used safely and effectively.

Yates says Merck is taking its commitment to responsible beef one step further by developing Best Management Practices (BMPs) to “keep people’s eye on the ball” with regard to mitigating stressors during the final weeks of cattle feeding that could affect animal health or wellbeing.

“Feeding and nutrition, cattle management, selection of cattle, low stress animal handling – whether you’re talking about the feed trough, the pasture, transport, cattle holding pens at the packing plant or anywhere in between, it’s kind of trying to capture the breadth and scope of all that into something the feedyard level can be implemented,” Yates says.

While the certification plan covers practices that are “critical for the use of the product,” the BMPs, Yates says, were designed to be discussed and adopted to meet the various needs of the feedyard.

Another step in the five step plan is to have a third party principle investigator conduct an extensive in-field use study of the product. Yates says Merck chose to wait until receiving FDA approval of the component feeding label, and advisory board approval of the certification plan.  The board suggested that BMPs be part of the five step plan. The next step will be to “gain concurrence” through various segments of the industry, from retail to food service, packers and feeders, before initiating the in-field study.

“When we have sufficient alignment so we can conduct a proper study to assess the safety and well-being of the use of the product – we’ll move forward,” Yates says.

Finally, a key topic for the advisory board to review surrounded alleged mobility issues in cattle fed Zilmax. Yates says the challenge with addressing the topic, however, was that there was no standardized system to measure mobility. Through working with third-party evaluators as well as animal wellbeing experts, a mobility scoring system has now been developed. The four-point system, with one being an animal with normal mobility and four being an animal that does not move well, will become an “industry standard”.  Yates notes that there will be videos and other training materials available through the American Meat Institute.

“We’re very proud to have been a part of that and to bring something to the industry that gives us a tool to go and make assessments in a uniform way – that’s really important for the industry if we’re going to continuously improve what we do,” Yates says.

Merck voluntarily pulled the product from the marketplace in August 2013 and continues to work to add to the data that exists for Zilmax.

“What we live by here is the passion we have for the business and our responsible beef commitment,” Yates says. “With the help of the advisory board and industry experts, they’ve helped us guide various standards and guidelines for proper use. It’s the right thing to do for the cattle, the customer and the industry.”

In accordance with FDA guidelines, a notice of approval for the component feeding label will be published in the Federal Register.