Pharmaceuticals giant, Merck and Co., facing questions from the cattle industry about the effects of its Zilmax feed additive on the health of cattle, on Tuesday responded with plans for a new quality control program to ensure the popular weight-adding drug is properly used.
The news comes a week after Tyson Foods Inc. declared it would stop accepting Zilmax-fed beef given some cattle were observed arriving at its slaughter facilities with signs they were having difficulty walking or moving.
Tyson Foods, the nation's largest meat processor said the decision was not made over food-safety concerns, and the company said it did not know exactly what was causing the animals behavior, but Tyson officials said that animal health experts have suggested that the use of Zilmax may be one possible cause.
That, in turn, has Tyson's cattle suppliers faced with a choice of sticking with Zilmax and selling to other packers, or switching to a less-powerful alternative feed supplement, or even dropping the type of drug known as a beta-agonist such as Zilmax altogether.
Beta-agonists are a class of drug approved and deemed safe by the U.S. Food and Drug Administration and long used by the livestock industry to add weight to cattle, pigs and turkey in the weeks before slaughter.
The class of drugs has come under scrutiny in recent months over concerns by Tyson, and JBS USA, another large cattle processor, when some animals were observed showing signs of distress and had difficulty walking after being fed beta-agonist additives. On Monday, Reuters reported that JBS USA's top animal health executive, at an industry conference last week. showed a video of cattle having difficulty moving and showing signs of lameness.
An FDA spokeswoman told Reuters Tuesday that the agency requires drug companies to report adverse drug events to the FDA. The agency declined to discuss whether it will investigate reports of animal behavior publicly discussed by Tyson and JBS in recent days.
While Tyson announced its change only last week, there are some signs that the company has quietly been expanding its supply of beef free of beta-agonists.
According to several feed lot operators interviewed by Reuters, the company began paying some feeders premium prices about six months ago to supply cattle that had not been fed beta-agonists.
A feed operator in Kansas, who declined to be identified by name because of concerns that "this could be a big political issue," said he plans to discontinue Zilmax use and instead exclusively use a competing beta-agonist, Eli Lilly & Co.'s Optaflexx.
"The whole deal don't matter to me one way or the other because their issue is not with Optaflexx," the cattle feeder said.
Herman Schumacher co-owner of L.D.L. Cattle Company, a 10,000 head privately-owned feedlot in Ipswitch, South Dakoa, said he has raised cattle free of beta agonists since beginning the business in 1986. Six months ago, he said, Tyson without any explanation began offering him a premium on cattle that had never consumed beta-agonists.
Schumacher said he expects Tyson's rivals to discontinue the use of beta-agonists, too. "Other packers have not floated out of this (Zilmax) yet, but with Tyson taking the lead on this I think the others will follow," he said.
The National Cattlemen's Beef Association, the beef industry's trade group, said in a statement said its members base their feed decisions "on science, not speculation. At this time, there is no scientific basis for saying the use of beta-agonists caused the animal welfare concerns cited by Tyson in their decision to stop buying cattle fed Zilmax."
After Reuters' report Tuesday, Merck's animal health unit said it will require cattle feeders that use its drug Zilmax to undergo additional training as part of a five-step plan to deal with mounting questions over possible negative effects from the drug.
The company also said in the next 30 days it will re-certify feed lot operators that use Zilmax, a process designed to make certain customers safely use the drug when feeding cattle. Merck also will launch what it termed a "scientific audit" that will follow Zilmax-fed cattle from the feed yards to the packing plant to determine potential causes of lameness and other mobility issues seen by Tyson and JBS.
