The recent decision by Merck Animal Health to remove the beef growth enhancer Zilmax from the marketplace while also maintaining that it is safe is bound to send confusing signals.
On one hand, to remove a product that has been approved in Canada and the United States would seem to compound the fears that Zilmax is causing lameness in cattle, despite lack of evidence.
Merck’s decision followed Tyson Foods’ announcement that it would no longer accept cattle that had been given the growth promotant because it had noticed larger than usual numbers of cattle showing difficulty moving, which it said may be attributed to Zilmax.
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On the other hand, Merck could ill-afford to wait for studies before taking action. If something previously unfound turns up in the new studies, the company will have left itself open to criticism for not acting at the first sign of trouble.
Consider it, then, a pre-emptive public relations strike.
Consider, as well, that if Merck had kept Zilmax on the market, it would have had to weather the storm until promised new studies are complete. Animal welfare issues are hot button points with the public, and any company that is perceived as being intransigent when there is even a possibility that a product could be causing harm could be embarking on an unwinnable public relations war.
In the end, the long-term reputations of Zilmax and Merck, not to mention the welfare of animals, likely would have taken priority over a year or so of missed sales by temporarily removing Zilmax from the market.
But whether Zilmax, a growth enhancer designed to convert feed to more muscle and less fat, is actually to blame remains uncertain.
There have been allegations in the past about these types of growth promotants, called beta agonists, and their tendency to make beef tougher. The other beta agonist on the market, Optaflexx, continues to be used and has not been subject to similar allegations.
Some have also alleged that Tyson’s decision to ban Zilmax was a play for new international markets, such as the European Union and Japan, which do not accept animals fed growth promotants.
Cattle producers have used Zilmax for years. When fed at the recommended dose, cattle showed a carcass weight gain of 24 to 34 pounds each and improved yield grades, which means getting the highest percentage of the more sought-after retail cuts.
That added edge in production, as well as shorter feeding times, which can mean less water, less feed use and less waste produced, have made Zilmax important in an industry with notoriously tight profit margins.
There has also been talk that Zilmax at the proper dose is not to blame at all. Instead, its overuse is the crux of the problem. That potential issue should be addressed by the company’s five-point plan and increased monitoring.
Part of the five point plan is to provide new training for feeders, nutritionists and veterinarians who use Zilmax.
Merck also plans a scientific review to monitor feeding of Zilmax, which entails following identified animals from the feedlot to packing plants.
It will work to update appropriate management practices to include nutrition, feeding goals and animal handling.
It will form an advisory board made up of representatives from feeders, packers, cow-calf operators and animal health experts.
It plans to share all of its findings.
Merck’s plans to review Zilmax and provide additional training could provide new insights on the advisability or inadvisability of continuing to use it.
The findings cannot come quick enough. An industry is anxiously awaiting the results. However, future actions should be guided by calm heads and must be based on science.