A Feeder’s Perspective On Beta Agonists

The voluntary removal of Zilmax from the market left several cattle feeders scrambling this past year. For Cactus Feeders it meant a technology that had successfully added profitability to 6 million head of cattle since 2006 was no longer available.

Hot carcass weight can increase by up to 32 lb. when zilpaterol is fed, says Kendall Karr, director of nutrition services at Cactus Feeders. In addition, the yield of red meat from the fabrication process increases by 1.5% or an additional 35 lb. per head harvested.

In order to recuperate this loss in red meat production, cattle would have to gain an additional 81 lb. of live weight when not fed a beta agonist. Not feeding zilpaterol translates into large losses in meat production for a company that feeds more than a million head of cattle each year.

(Read Beta Agonist Anxiety)

"To put it in Cactus Feeders’ terms, it would mean we’d have to feed about 40,000 more cattle each year to maintain the carcass production—or about 60,000 more cattle to maintain the boneless meat production that we’d have gotten with the beta agonist," Karr says.

From a sustainability angle, to gain the 81 lb. of live weight, it requires an additional 500 lb. of dry feed and 280 gal. of water per calf. Not to mention a $60 per head feeding expense increase.

"Bottom line—we’d have to pay $8.60 less per hundredweight for a feeder animal to be able to breakeven," Karr adds. "Now take those numbers and multiply that by a million head per year, which we feed." 

Studies on beta agonists are more commonly seen at the university level, but since 1999 Cactus Feeders has been examining zilpaterol at their research facility. During that time, 80,000 cattle have been through 31 trials involving beta agonists.

"We have understood the importance of research for our business," Karr says. "With any technology comes great responsibility. At least for us at Cactus Feeders, before we fed the first gram of either one of the beta agonists, there was a lot of thought that went into how it was going to be done and what precautions were going to be made."

For the time being, Optaflexx is still available for use. Cactus Feeders has fed more than 2 million head with the product since 2004.

Karr points out in the 15 years Cactus Feeders has researched beta agonists, and the 10 years they have fed beta agonists, there has not been one issue concerning feeding or handling of the product.

"As cattlemen it is our job to be observant. It is our job to take care of the cattle and make sure every day they are in our charge we are doing the things necessary for their well-being," Karr says.

"From our perspective we’ve just not seen anything that would suggest there is a problem with beta agonists and animal well-being," he adds.