Effects of Ionophore Supplementation of Yearling Steers Gain on Annual Rangelands in CA - 6003

Principal Investigator: Larry Forero, UCCE Shasta County

Ionophores are frequently fed to improve beef cattle weight gain. Data from a replicated study in the Flint Hills of Kansas showed an increase of 0.30 lbs per day for treated cattle over control animals. Ionophores have been shown to improve cattle gains on winter wheat as well as irrigated pasture. This study will be the first to establish if there is an increase in performance from the use of ionophores on growing beef cattle pastured on annual grassland in CA. An estimated 650,000 head of weaned calves are grazed during the winter on the annual grassland of CA, giving this project much potential benefit in California and other western states with annual rangeland.