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CME: Jury Still Out on Zilmax

CME: Jury Still Out on Zilmax

15 August 2013

US - More information is required before evidence based conclusions can be drawn around the suitability of feeding cattle Zilmax, according to Steve Meyer and Len Steiner.

With the benefit of a few deep breaths, some thought and observing a lot of screaming and yelling, today we revisit the great Zilmax controversy of 2013, write Mr Meyer and Mr Steiner.

To recap, here is what has transpired so far:

  1. Tyson Foods announced on August 7 that it would stop accepting slaughter cattle that had been fed Zilmax, the trade name for zilpaterol, a beta-agonist feed additive used in the final days of the feeding period to increase lean muscle gain and improve feed efficiency. The announcement did allow that the suspension may be temporary.
  2. The decision was based on several instances in which cattle delivered to Tyson had difficulty walking. The Tyson announcement said nothing about product quality, palatability or food safety.
  3. Only zilpaterol was targeted by Tyson. Ractopamine, another beta-agonist and the active ingredient in Optaflexx, was not mentioned in the announcement, and Tyson has since stated that it intends to continue to accept Optiflexx-fed cattle.
  4. Cargill, JBS Swift and National Beef, the other three of the “big four” beef packers, have all announced that they intend to continue to buy cattle fed zilpaterol. Cargill, which at one time did not buy zilpaterol-fed cattle due to meat quality concerns, made its announcement quickly last week. The others have followed suit this week.

As we pointed out in the August 8 edition of The Daily Livestock Report, the supply impact of Tyson’s decision was very dependent upon whether other packers followed their lead. Combine the competitors’ decisions to not follow Tyson’s lead with Tyson’s continued acceptance of Optaflexx fed cattle, and we don’t see where there will be a material impact on fed beef supplies come September 6.

The only change would be a slight reduction in weights (our sources say 6-8 pounds, on average, per head or about 1 per cent) for the 25 per cent or so of all fed cattle that are processed by Tyson. Those figures would suggest a total decrease of less than 0.25 per cent.

Zilmax’s manufacturer, Merck Animal Health, defended its product and has announced a five-step “Ensuring Responsible Beef” program that includes immediately re-certifying every individual that feeds Zilmax to cattle; initiating a scientific audit following cattle fed Zilmax from the feedyard to the packing plant “to determine potential causes of lameness and other mobility issues”, reinforcing appropriate management practices, creating the “Merck Animal Health Advisory Board” comprised of feeders packers, cow-calf operators and animal health and nutrition experts and, finally, sharing all findings publicly.

It is ironic that Tyson’s announcement came just one day after a meeting of beef industry participants in Denver to discuss beta-agonists and their impact on animal welfare. We understand that the meeting was far from harmonious with some parties defending the additives as scientifically proven and sound while others cited numeroous instances where the product had caused severe lameness.

It strikes us that the fact there was a meeting to discuss beta-agonists signifies some serious challenges. Tyson’s subsequent (and, as far as we know, unrelated) announcement the next day just confirms that.

The resolution of this situation is important. The beta-agonists are a major reason for the sharp increase in slaughter weights observed in early 2012.

It is hard to find any other reason that weights would increase sharply in the face of high feed costs and then remain high even when feed prices rose to record-high levels. In addition, the extra carcass yield provided by beta-agonists is an important factor in the economics of packing plants.

Ractopamine has been a contentious issue for beef, pork and turkey exports this year with China initiating a program to “certify” pork to be ractopamine free and Russia banning imports of US beef, pork and turkey, ostensibly due to the use of ractopamine.

Most observers would blame the Russian ban more on politics and protectionism but the use of beta-agonists by US producers gave the Russians a ready-made scapegoat — and one that impacted three species!

Some, like Cargill, have been concerned all along that beta-agonists in general and zilpaterol in particular were having negative impacts on beef quality. As can be seen below, any negative impact is not apparent in USDA's quality grading data, but readers should realize that the concerns were specifically over tenderness and palatability, two characteristics that are not directly measured by quality grade.

The jury is decidedly out on this one. We don’t know everything that happened to those cattle but urge the parties involved to find out. Tyson has a long record of accepting and defending scientifically valid, modern technology. If this one is indeed safe for the animals, let’s find out what went wrong and get it fixed so the industry, its customers and its critters can all benefit.

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