UPDATE: Cattle Growth Promotants – New Development Unfolds

If you’ve been following the news closely over the last few weeks, you have probably heard about an interesting development in the beef industry.Earlier this month, Tyson Foods Inc. – the biggest beef processor in the US - announced that it will no longer accept cattle that have been fed Zilmax (a type of growth promotant, also known as a beta agonist that promotes fast weight gain).

In their announcement, they state that there have been some instances of cattle arriving at the plant that have difficulty walking or are unable to move, and this has lead them to stop accepting cattle fed Zilmax. (Note: Whole Foods Market® first started prohibiting growth hormones in the early 1980’s).  

The manufacturer of the drug – Merck Animal Health – responded that their product had a 30-year history of testing but that they would conduct audits and further research. However, a few days later Merck announced that they would temporarily suspend sales of Zilmax in the US and Canada while they implement the auditing process.

Why should you care about this latest development? Earlier this year, I wrote about the use of growth promotants opens in a new tab in the cattle industry and how they impact the beef we eat.

To be clear, Whole Foods Market prohibits the use of growth promotants/beta agonists in our entire meat supply, as well as antibiotics, ionophores, growth hormones and sulfas. Every beef ranch that supplies cattle to be sold at Whole Foods Market undergoes an on-site third party farm audit every 15 months as part of our strict animal welfare requirements opens in a new tab – and part of that audit process checks to make sure these prohibited substances are not used.

While the meat you buy at Whole Foods Market does not contain these drugs, it is very concerning that growth promotants like Zilmax are widely used in the beef industry, not only from an animal welfare perspective but also because of its effects on meat quality and the unknown implications to humans of eating beef fed growth promotants.

Tyson’s surprise announcement has caused quite a stir in the industry and has been called a “game changer” by analysts. According to industry estimates1, 2 more than 70% of US cattle are fed growth promotants and cattle can pack on the pounds - gaining 30+ lbs in 20-40 days. It is uncertain whether feed yards will switch to an alternative growth promotant or stop using them altogether, but there is speculation that there will be beef shortages and higher prices as a result of the suspension of Zilmax in the market. After almost a decade of using growth promotants, it will be interesting to follow how the 75,000 US cattle feed yards handle this latest development. The use of Zilmax is an example of how the “Concentrated Animal Feed Yard” system, based on intensive consumption of corn by confined cattle, is broken.  The competition for profits between ranchers, feeders and processors has created a system where each is looking for an advantage over the other, rather than a system based on a win/win/win philosophy.  This is driving operators to make decisions based solely on economics rather than quality, animal welfare or consumer interests.       

More than 80 countries have banned the use of growth promotants/beta agonists already. And at Whole Foods Market we prohibit their use too. Should growth promotants continue to be allowed in the US and Canada? Tell us what you think!


1 Joe Roybal and Wes Ishmael, “Capping An Eventful Nine days, Merck Halts Zilmax™ Sales opens in a new tab,” BEEF (August 20, 2013).

2 “Merck makes game-changing announcement on Zilmax,” Meating Place, (August 16, 2013).


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