Response of beef calves to handling and restraint in a chute

Ninety-eight Polled Hereford calves, averaging 215.13 ±1.96 days of age at weaning and 92 Polled Hereford calves averaging 381.17 ± 1.98 days at postweaning were the subjects of an investigation of behavioral responses at the Tobacco Experiment Station (TES). At the Plateau Exper-iment Station (PES), 82 purebred Angus calves averaging 386=14 ± 1.83 to 223.66 ± 1.93 days at weaning and 91 purebred Angus calves averaging 386.14 ± 1.83 days at postweaning, also were included in the study. At weaning, three variables, pulse rate, respiration rate and visual score of behavior, were recorded for each calf in an approach chute and in a squeeze chute. At postweaning, body temperature also was measured. The differences in approach chute and squeeze chute values, as well as the means of the approach chute and squeeze chute values, were examined as to their correlation to production. In general, the means of the variables seemed to be more informa-tive with respect to response of the calves than did the differences. This is believed to be due to an elevated response in the approach chute, such that further elevations in response to psychological stress were limited. The relationship of the variables to each other and to production traits differed between stations and times. However, age as an effect could only be examined within weaning and postweaning times, and breed differences could not be examined, since time, breed and station were confounded. At TES, the variable with the treatest relationship to pro-duction seemed to be mean respiration rate. At PES, mean pulse rate appeared to be the most important variable at weaning. At postweaning, the calves responded differently to being worked. It can be hypothesized that the responses at postweaning-were reflective of environmental stimuli other than; psychological stress. Possibly at postweaning, the response to being worked was a response to mild psychological stress and that other physiological factors, such as sex, may in that case, over-ride the effect of a stress response.