Relationship between Temperament and Performance Traits in Yearling Cattle

To examine relationships between exit velocity (EV, objective measure of temperament) and performance traits, calves were weighed 14 days prior to weaning, at weaning, 128 days post weaning, and at time of carcass measurements. Exit velocity obtained on day -14 and carcass ultrasound measurements (n = 6) obtained on day 208 and carcass harvest measurements (n = 12) obtained on day 349 were used to determine correlations between EV, performance and carcass measurements. Exit velocity showed a tendency to be negatively correlated (P \u3c 0.15) with weaning weight (r = -0.40), but not correlated (P \u3e 0.05) with average daily gain post 128 days. Exit velocity was not correlated (P \u3e 0.05) with carcass ultrasound measurements or with yearling weight. Exit velocity was negatively correlated (P = 0.04) with carcass weight (r = -0.65). Although, EV was not correlated (P \u3c 0.05) with carcass harvest traits of back fat and longissimus muscle area, results indicated more excitable cattle could have less back fat and smaller longissimus muscle area. Results suggest with additional numbers EV may be useful as an objective measure of temperament to sort calves into specific outcome groups that differ in carcass quality traits