During the recent Colorado Nutrition Roundtable at Colorado State University, several graduate students from CSU, University of Nebraska and University of Wyoming presented results of their research. Paul Repenning, a CSU student, outlined results of his study on the relationship between behavioral traits and performance in finishing steers.
The trial evaluated cattle behavior using both subjective and objective measurements, and examined the relationship between those behavioral traits and average daily gains and dry-matter intake.
The subjective measurement used chute scores in which workers rated cattle in the chute from zero to five, with zero indicating calm and five indicating aggressive behavior. Subjective gait scores used a four-point scale, with one equaling walk, two equaling trot, three equaling run and/or jump and four for cattle that fell as they exited the chute.
Objective measurements included the number of seconds in the chute and electronically measured exit velocity.
The researchers tested a group of 186 Bos taurus and Bos indicus crossbred steers, weighing them every 14 days for a 70-day trial period. They used a Grow Safe bunk system with radio-frequency identification to measure individual intake, and employed low-stress animal-handling methods throughout the trial.
The researchers found that exit velocity was negatively correlated with average daily gains and dry matter intake in the feedyard, meaning cattle that ran, jumped or fell out of the chute showed poorer performance than those that waked or trotted. In this trial, the objective, electronic measurement for exit velocity had the strongest correlation with average daily gain, but the subjective gait measure, with scores assigned by processing crews, also was negatively correlated with daily gains. The researchers conclude that subjective gait scores can serve as an adequate representation of objective exit-velocity measurements.
In future research, the team hopes to collect the same subjective and objective behavior measurements at weaning, and evaluate their correllations with lifetime average daily gains, feed intake, residual feed intake and carcass quality in beef steers. If measurements of behavioral traits early in a calf’s life provide a reliable indicator of lifetime performance, ranchers potentially could incorporate them into decisions regarding bull selection, heifer selection, cow culling, calf management and marketing.