The U.S. Food and Drug Administration (FDA) has granted approval for feeding Rumensin to dairy cows in component-feeding systems. These systems include supplements that are fed in the parlor, in electronic feeders or as a topdress. The minimum feeding rate for these supplements, which can be fed both to dairy cows on pasture and dairy cows in confinement, is one pound per head per day.

The new label for Rumensin has updated mixing and feeding directions for these supplements, which the FDA calls Type C medicated feeds. In addition, the directions now include individual-cow ranges for Rumensin feeding, with levels from 185 mg/hd/day to 660 mg/hd/day approved for lactating cows and from 115 mg/hd/day to 410 mg/hd/day approved for dry cows.

"These label changes provide added flexibility and helpful guidelines when feeding Rumensin to increase milk-production efficiency," says Howard Green, dairy technical alliance manager, Elanco Animal Health. "As a result, even more dairy producers will be able to help their cows get more energy from every pound of feed they eat. And they'll see the greatest benefits when feeding Rumensin continuously to both lactating and dry cows, just as indicated on the FDA-approved label."

Nutritionists and producers may continue to feed Rumensin to lactating and dry cows in TMRs at a rate of from 11 g/ton to 22 g/ton on a 100 percent dry matter basis.

In addition, The FDA also has expanded the Rumensin label to allow feeding it to dairy replacement heifers that are raised in drylots. This is in addition to heifers raised on pastures who could already be fed Rumensin. The feeding directions for heifers remain the same - from 50 mg/hd/day to 200 mg/hd/day with the Rumensin concentration in Type C medicated feeds ranging from 25 g/ton to 400 g/ton.

"With more and more dairy heifers being raised in confinement situations - such as on drylots, this expansion of Rumensin's label claim creates an important new opportunity," adds Green. "Now producers can profit from both the increased weight gain and the coccidiosis control that comes from feeding Rumensin to heifers in drylots. And, they can enjoy the convenience of feeding a single ionophore to help meet the energy needs of dairy cows and growing heifers."

To read the label in its entirety, visit Rumensin can be purchased through traditional animal-health and nutrient-supplier companies.

Elanco Animal Health