Department of Animal Science


Date of this Version

January 2007


Published in 2007 Nebraska Beef Cattle Report. Copyright © 2006 The Board of Regents of the University of Nebraska.


Eight ruminally fistulated steers were used in a metabolism experiment to determine effects of an essential oil feed additive in altering steer ruminal fermentation characteristics and nutrient digestibilities. Yearling steers were fed three treatments: 1) Control (CON) 2) CRINA RUMINANTS AF (CRINA) and 3) Rumensin® (RUM). There were no differences in DMI, OM intake, total tract DM and OM digestibilities, or pH among treatments. Steers receiving the CRINA treatment consumed 24.5% fewer meals than CON. Ruminal acetate was greatest and total VFA concentrations tended to be greatest for CRINA treatment. Acetate:propionate was 1.68, 1.49, and 1.43 for CON, CRINA, and RUM, respectively, suggesting addition of CRINA RUMINANTS AF favorably alters rumen fermentation end products without negatively affecting intake or rumen pH.