Abstract
Most dairy calves are housed individually in their early ontogeny but there is an increasing interest in housing calves socially. Social housing has many positive effects on calf welfare including an advantage of social buffering, i.e., when negative effects of stress are mitigated through social support of familiar conspecific. So far, social buffering has not been tested in relation to stress after disbudding, a painful husbandry procedure performed in young calves. Therefore, the effect of pair versus individual housing on calves’ reaction to disbudding was investigated. In total 50 female calves housed either individually (n= 14) or in pairs (n= 36, 18 focal) were used. Calves were hot-iron disbudded with a local anesthetic and their behavior in home pens was recorded 24 h pre- and post-disbudding. Feeding, ruminating, resting, exploration, play, self-grooming, and pain-related behaviors were quantified during eight 20 min intervals during the 24 h periods pre- and post-disbudding. In pair-housed (PAIR) calves social resting, active and passive allo-grooming were additionally recorded. Concentrate intake was measured 24 h pre- and post-disbudding. The changes of pre- and post- disbudding behaviors as well as differences between individually housed (INDI) and PAIR calves were tested by general linear models. The differences in pre- and post-disbudding behaviors of PAIR calves were tested by paired t-test. We found that head rubbing (t=-5.14, P<0.0001) and head shaking (t=-3.33, P=0.004) increased after disbudding. Feeding increased only in PAIR calves (t=-2.95, P=0.016) which also resulted in a difference between treatments with PAIR calves fed more than INDI calves (F1,18=12.27, P=0.003). We did not find any other significant differences. Our results provide the first evidence that housing treatment affects calves' reactions to disbudding, with possible indication of social buffering.