Animal Science Department


Date of this Version

January 2008


Published in 2008 Nebraska Beef Cattle Report. Copyright © 2007 The Board of Regents of the University of Nebraska.
Available online at


Two individual feeding experiments were analyzed for the relationship between metabolizable protein (MP) balance and feed efficiency (G:F) in individually-fed steers and heifers. In Experiment 1, 29 crossbred steers were fed steam-flaked corn (SFC)-based diets containing either 0% or 1.2% urea (DM basis). In Experiment 2, 75 crossbred heifers were fed SFC-based diets with either 0% or 1.5% urea. The NRC (1996) MP model was used to determine individual degradable intake protein and MP balances. In both experiments there was a negative relationship within treatment between MP balance and G:F. These results were not expected, and three potential causes were proposed: conversion of MP to net protein; ruminal pH; and/or residual feed intake.