Or so the industry suspected.
Since 2013, Zilmax, or zilpaterol hydrochloride, has not been re-released to the market after Merck Animal Health voluntarily pulled the beta-agonist, citing a commitment to further examine the safety of a product that was arguably one of the leading feed efficiency technologies in the industry.
Anecdotal evidence pointed to fat cattle adversely reacting to Zilmax during the withdrawal periods just prior to harvest.
However, since this evidence came to light in August 2013, thus spurring a chain of events that would lead packers to ban Zilmax-fed cattle and Merck’s voluntary removal of the compound, new evidence suggests the prevalent lameness in cattle arriving at harvest facilities was due to various factors other than Zilmax.
Numerous formal research studies have been conducted outside of Merck’s internal audit in efforts to better understand what was causing high numbers of non-ambulatory animals arriving at harvest facilities.
Most notably, Dr. Daniel Thomson, DVM, Jones professor of production medicine and epidemiology, Kansas State University College of Veterinary Medicine, has been a part of numerous trials over the last four years that all suggest zilpaterol hydrochloride was less a culprit and more of an industry scapegoat.
Thomson candidly offered his insight, perspective and a lesson the entire industry can learn from this situation.
What has your research shown to be the primary cause of the high rates of lame, non-ambulatory cattle arriving at harvest facilities in 2013?
Thomson: After four years of great research, we’ve learned that fatigued cattle syndrome (FCS) has more to do with cattle size and degree of finish, how cattle are handled at slaughter, heat stress associated around the shipping and loading time, and more. All of these variables play a much larger role than beta-agonists in the problems we have seen. We still see fatigued cattle syndrome.
Not near at the rate as we have seen in the past, but I attribute that more to defining the actual issue, providing education, and now we prevent it.
Our research has shown if the circumstances are right, we can create fatigued cattle syndrome in cattle that are not fed a beta-agonist, and if cattle are handled appropriately, we can prevent fatigued cattle syndrome even if they are exposed to beta-agonists.
So feed efficiency technologies weren’t the sole cause of lame cattle arriving at harvest facilities?
Thomson: If it was the technology such as zilpaterol causing the FCS issues, why would we only remove one of the compounds in that class of growth promoters? Ractopamine has remained on the market and actually has been fed at a higher level over the last few years to increase its potency.
We are using it in most of the cattle on feed, so obviously FCS is not a beta-agonist technology [issue] but rather, in the end, how we were handling these large finished cattle during summertime heat.
I think that, to me, that’s kind of the end game. We spent four years doing research on the subject, we have had three or four students publish dissertations or theses on the subject to show what the main risk factors are associated with the syndrome that was being seen in 2013, so it wasn’t product-specific. Zilmax should be back on the market.
How has fat cattle management changed?
Thomson: In the end, once we identified the problem, we have seen holistic FCS prevention programs being put in place in feedyards and packing plants.
The beef industry has spent so much time focusing on the first 30 days of the feeding period; now we’re finding that we’re spending a lot more time focusing on the last 30 days of the feeding period and specifically maybe the last day.
We’re staging cattle closer to load-out; we’re walking cattle to the load-out; we’re taking the time to provide more low-stress handling at load-out at time of shipping. We’re making adjustments to our fat cattle trailers.
We’re very conscious of how we unload those cattle at the slaughter facilities, and we’re making sure they have shade and misters and ample water tank space available in our holding pens at the packing plant. What I am seeing is: Now people are making the appropriate adjustments to the welfare of the fat cattle during the last day of their life.
What effects has the removal of Zilmax from the market had on the industry as a whole?
Thomson: We lost a good product, and it was based on some circumstantial evidence. I think the benefit from this is: We have learned not to make knee-jerk reactions. Before we make these types of decisions, we [as an industry] really need to do our research and provide due diligence so we don’t lose technologies that can help improve the beef industry.
What we’ve lost is some pricing on feeder cattle, red meat yield and feed efficiency by losing zilpaterol.
I think technology is good. And science is good. And understanding we have to trust each other and we’re all working for a common good for the beef industry is important. When we have one technology thrown under the bus, it makes it easier for the second or third or fourth to be lost.
The people who really lose when technology in the cattle-feeding operations are lost are cow-calf producers and our consumers. The money is neither created nor destroyed. Everyone between the rancher and the consumer is a margin business – the stocker, the feeder, the packer, the retailer.
If the efficiency in feeding the animal is decreased, either the cow-calf producer will get paid less for the calf coming in to the feedlot or the consumer will get charged more for the beef going out to the store.
Why is this important to the industry?
Thomson: We did the FCS research and showed it wasn’t caused by the technology. So we should bring the technology back to show good faith to companies that take the responsibility like Merck did to remove the product until we know the answer. I think that is the fair and equitable thing to do.
I think it’s important that when a company takes the responsibility, steps back and investigates the problem, they should be rewarded for being stewards of their product and our industry. Zilmax was a huge product for Merck; they didn’t have to say, “We’re going to take a break.” But they did because they wanted to get it right.
If we don’t [bring Zilmax back], companies will never remove a product to do research because we will have shown that when you do, you will never get the product back, and we want companies to act responsibly. We want them to say, “If something isn’t going right, whoa; let’s take a break and figure it out.”
And so I think [we need] to set the example going forward for our industry – what if it’s ractopamine? What if it’s steroid implants? What if it’s feedlots? Let your mind go crazy, but when we sit back and do nothing to help them after we have done the research and we have the findings, we are turning our back on a responsible partner. 
Danielle Schlegel is a freelance author based in Whitewood, South Dakota. Email Danielle Schlegel.
