Merck wants to test Zilmax but beef industry is reluctant

Merck wants to feed its controversial feed additive Zilmax to 240,000 US cattle to prove it is safe. But they face a huge problem: giant meat processors like Cargill don’t want to touch animals fed with the drug.

Merck plans to conduct the biggest ever test of its kind in an effort to reintroduce the weight-adding drug into the United States and Canada after suspending sales last August. A test herd of this size is currently worth up to US$500 million.

Feedlot owners, however, are reluctant to participate in the study until they get a guarantee that slaughterhouses will be willing to buy the Zilmax-fed animals. “I’d be happy to sign up, just as soon as Merck tells me who is going to pay me after they’re done,” said a feedlot owner in Texas. “It’s been a horrible time, with the drought. I can’t afford to give away a steer, let alone hundreds.”

Cargill and Tyson Foods two of the world’s largest beef processors, told Reuters their stance on Zilmax had not changed since last autumn, when they stopped accepting cattle fed the drug following reports it may cause lameness. Together the two companies control 37% of the daily US beef processing capacity.

Reuters reported in December that Tyson stopped taking Zilmax-fed livestock after more than two dozen animals that had been fed the drug arrived at one of its slaughterhouses with missing hooves.

The beef processors said their ban would remain until Merck had scientifically proven that Zilmax was safe for animals. They also want certainty that key export markets in Asia and elsewhere will accept such beef products.

Merck has said it is confident in the “safety and performance” of Zilmax. The US Food and Drug Administration has deemed the drug safe for both animals and humans.

With Zilmax off the market since last August, rival pharmaceutical firms have grabbed market share. Many US feedlots have switched to ractopamine-based Optaflexx, made by Merck rival Eli Lily & Co.’s Elanco Animal Health unit.

Reuters UK