“You can get more energy from the same feed, whether you’re feeding it to a lactating cow or developing a replacement heifer,” says Ron Randel, Faculty Fellow of Reproductive Physiology at Texas AgriLife. “The net result is better performance and better reproduction.”

Randel is talking about the proven opportunity that comes with supplementing replacements and mature cows with an ionophore. He and fellow researchers at Texas A&M University were among the first in 1977 to document the potential of feeding the ionophore compound, monensin, to heifers and cows. For the record, Rumensin® (monensin) is the only ionophore labeled for use in both growing heifers and mature beef cows.

If you’re unfamiliar with ionophores, they are antimicrobial compounds that inhibit the growth of rumen organisms that disrupt rumen fermentation and function; they help capture more feed energy and decrease protein erosion.

Depending on the research, ionophores in stocker diets increase average daily gain by 0.15 to 0.3 lbs./day and increase feed efficiency by 2-7%. That’s feeding at a rate of approximately 125-200 mg/day at a cost of pennies per day. Besides the gain, ionophores also reduce the incidence of coccidiosis, acidosis and bloat.

Increased feed efficiency means cattle attain the same performance on less feed or more performance with the same level of feed consumption.

“In all of the research we conducted, we didn’t find a single downside to the use of ionophores in either replacement heifers or lactating cows,” Randel says.