Some effects of repeated handling and the use of a mask on stress responses in Zebu cattle during restraint

The objective of this investigation was to evaluate the effect of repeated handling and the use of a mask on the order of entry, temperament, cortisol concentration and heart and respiratory rates of Brahman cattle during restraint in a squeeze chute. In the first experiment, 18 cows were restrained in the chute for 10 min on 19 test-days and blood samples were collected during five of the trials. Habituation to handling was reflected by a decrease in cortisol concentration as the study advanced (P < 0.01). In the second experiment. conducted 6 months later, animals were randomly allotted to two groups, alternating the use of a mask over test-days while restraining the cows in the chute for 3 min, Respiratory and heart rates were measured at the beginning and end of each 3 min trial. A blood sample was also taken at the end of each trial. Respiratory rates decreased while the animals were restrained and this decrease tended to be greater (P = 0.09) when the animals were wearing masks (3.06) than when not (2.2 breaths/min). Heart rates also decreased and more so for masked animals (10.6 beats/min) than for non-masked (5.0, P < 0.01). Cortisol values tended to be higher (9.9 versus 4.7 ng/ml, P = 0.08) when animals were restrained without a mask. Temperament scores were lower (P > 0.01) when cows were masked and have a relative high correlation (r = 0.58) with flight distance values, (P < 0.05). Finally, the order of entrance was found consistent over test-days, (P < 0.01). It is concluded that Brahman cattle: (a) habituate to repeat handling in a squeeze chute; (b) are less emotionally reactive when their eyes were covered during this process and (c) establish a repeatable order of entrance to the chute. (C) 2001 Elsevier Science B.V. All rights reserved.