Tyson Foods might have helped the US beef industry defuse a ticking time-bomb. Tyson’s decision to stop buying cattle fed the feed supplement Zilmax as of Sept. 6 stunned many in the industry. But while its decision was unilateral (other packers initially said they had no similar plans), some prominent members of the industry quietly applauded Tyson for its action.

That’s because there have been numerous questions about Zilmax since it first began to be used in US cattle feeding in 2007. Its benefits were and are well-known. The zilpaterol hydrochloride-based compound can add 24 to 33 lbs. of live weight to fed steers and heifers in their last 20 days of time on feed. It is said to add 1.4 percent in a carcass’s dressing percentage. It is said to double the percentage of carcasses that grade Yield Grade 1 and halve the percentage of Yield Grade 4s and 5s. So, it produces leaner beef.

It’s understandable then that after years of testing Zilmax and receiving approval for its use from the Food and Drug Administration, manufacturer Merck Animal Health began to market it aggressively to cattle feeders. At the same time, it needed to persuade packers and beef end-users that Zilmax did not adversely affect beef quality. So, it argued that use of Zilmax improves the yield of most sub-primals and decreases the percentage of trimmable fat.

There were concerns, however, that the result was less-tender beef than that produced without Zilmax or produced using another beta-agonist, Optaflexx (which began to be used after Zilmax). The Certified Angus Beef (CAB) program expressed such concerns in October 2010, citing feedback from some of its restaurant customers. CAB is, by far, the industry’s most-successful branded-beef program, so its remarks were taken seriously. But Merck iterated the results of its tenderness tests on Zilmax-produced beef, saying Zilmax had no impact on tenderness.

Animal-welfare concerns

Concerns also arose about the impact of Zilmax on cattle well-being, particularly if used more aggressively than Merck recommended and used at certain times of the year (such as during extreme heat). World-renowned animal-handling specialist Dr. Temple Grandin (a contributing editor to M&P) raised eyebrows when she stated her concerns about Zilmax’s possible effects on cattle. Perhaps not surprisingly, Tyson honed in on the issues that Grandin raised when it announced its decision Aug. 6 to stop buying Zilmax-fed cattle.

Despite these concerns, most but not all, cattle-feeding operations gave way to reluctant, other than more enthusiastic, use of the supplement. This evolution reflected the fact that high feeder cattle and corn prices in 2010 and 2011 began to erode cattle-feeding margins. Fed-beef processors were even more reluctant to accept Zilmax-fed cattle. But Tyson and JBS USA began accepting them in 2011 after intense debate within each company. JBS, the industry’s largest cattle-feeding operation, also started feeding Zilmax to some of the two-million cattle it finishes each year. Cargill Meat Solutions held out longer both as a major cattle feeder and fed-beef processor. But it started accepting Zilmax-fed cattle in late spring last year.

These uptakes meant that in 2012, an estimated 75 percent of all the cattle on feed in the US were being fed either Zilmax or Optaflexx. Some estimates are that their use by July this year was split 50/50. Merck says that its Zilmax sales in the US and Canada in 2012 totaled $159 million.

Despite, and perhaps because of, the widespread use of Zilmax, concerns persisted about how the general public might perceive its use. While both beta-agonists are deemed safe for animals and humans, some in the industry feared the social media might start blogging about “cattle on steroids” or spread some other distorted story about their use. Hence, some industry leaders deemed Zilmax’s use a “ticking time-bomb.” They had good reason to be concerned, given the social media’s destruction last year of Beef Products Inc.’s lean finely textured beef product.

Tyson, in a letter to cattle feeders, was clear that it based its decision on concerns about animal well-being. The letter noted, “our continued concerns about the receipt of cattle that become non-ambulatory or lame at some of our beef plants. There have been recent instances of cattle delivered for processing that have difficulty walking or are unable to move. We do not know the specific cause of these problems, but some animal health experts have suggested that the use of the feed supplement Zilmax, also known as zilpaterol, is one possible cause.”

Ironically, Tyson’s decision became public the same day a beef-industry forum examined the use and effect of the two beta-agonists. At that forum, Lily Callaway, a member of JBS’s animal-welfare team, disclosed that JBS had seen increased incidences of ambulatory stress in steers delivered to one of its processing facilities. But JBS later said it could not establish a direct connection between this event and the use of Zilmax.

JBS, Cargill, National Beef Packing and other fed-beef processors, no doubt, had intense discussions about what to do next. But subsequent events relieved them of a Tyson-like action. On Aug. 13, Merck announced its “Five-Step Approach to Ensuring Responsible Beef,” which would involve an extensive audit of the use of Zilmax. Just three days later, it said it was suspending sales of Zilmax in the US and Canada because it needed time to implement its audit.

Merck’s decision gave Cargill, JBS and National Beef a rationale for saying they will also stop buying cattle fed Zilmax. Cargill said on Aug. 22 the last of the cattle being fed Zilmax that are in its supply chain would be harvested by the end of September. Cargill will suspend purchases of Zilmax-fed cattle in North America, pending research being conducted by manufacturer Merck Animal Health. This will give producers adequate time to transition cattle currently being treated with Zilmax, it said in a statement on its News Center website. In turn, JBS and National Beef were said to have started informing their feedlot suppliers that they will stop buying Zilmax-fed cattle, in JBS’s case starting from Sept. 23.

While Cargill has not linked Zilmax to any specific incidents involving animal well-being, it does believe more research is necessary to answer recently raised questions regarding the use of this product, it said. Consequently, Cargill supports Merck’s decision to suspend sales of Zilmax in the US and Canada. Cargill was the last major beef packer to allow cattle fed Zilmax into its beef supply chain, in June 2012, it said. One reason Cargill was initially reluctant to accept cattle fed Zilmax was a series of extensive beef-tenderness tests that created concern about potential impact to product quality. Of the major US packers, Cargill harvests the lowest percentage of cattle fed Zilmax, it said.

What’s next?

How long the audit will take and suspension will last is anyone’s guess. For now, cattle feeders will likely move to using more Optaflexx and feed cattle to heavier weights as corn prices decline. Whether Zilmax is used again might depend on factors, including: whether Merck eventually deems it safe at lower usage levels; whether the beef industry feels it can increase carcass productivity gains without its use; and whether social media takes up the Zilmax story or not.

One side twist to Tyson’s decision was speculation that it took action for trade purposes, to get its beef into markets that ban US beef due to the use of ractopamine. This was untrue because Tyson will keep accepting Optaflexx-fed cattle (the ractopamine beta-agonist). But it threw the spotlight on Smithfield Foods’ decision in late May to sell the company to Hong Kong-based Shuanghui International Holdings Ltd. for $7.1 billion in cash and debt.

Smithfield and Shuanghui have shared ties since at least 2009 and last year discussed ways to deepen their ties. One obvious one was for Smithfield to start producing more ractopamine-free pork, which it could export to China (which has a ractopamine ban). Smithfield, which produced 15.8 million hogs in fiscal 2012, began talking publicly about raising more ractopamine-free hogs early this year. By June 1, it was producing half its hogs without ractopamine.

This was a clue to its next step, to sell to Shuanghui, which owns China’s largest meat-processing enterprise (it processes more than 15 million hogs annually). Some of Smithfield’s shareholders are fighting the proposed deal. But should it be completed, Smithfield will get an even more direct conduit to the colossal Chinese market and sell even more pork there. This, as Smithfield has emphasized, is positive news for the US pork industry, as more exports means potential expansion of the US hog herd.

Steve Kay is editor and publisher of Petaluma, Calif.-based Cattle Buyers Weekly (www.cattlebuyersweekly.com).