The effect of shearing in a hot environment on some welfare indicators in Awassi lambs

Abstract

The aim of this study was to analyze the effects of shearing on the individual behaviors and rectal temperature profile during the day at hot environment in Awassi lambs. Twenty Awassi male lambs were randomly allocated into shorn (n=10) and unshorn (n=10) groups (28.8 +/- 0.7 and 29.9 +/- 0.7 kg, respectively) and were kept indoor during the experiment. The physiological and behavioral response variables measured were rectal temperature, standing, lying, feeding, ruminating, drinking, locomotor activity, and elimination. The effect of day, time of day, and all interactions on rectal temperature were found significant (P<0.001). The effect of shearing on the rectal temperatures of lambs was tend to be significant (P=0.06). Overall, unshorn lambs showed more frequencies of locomotor activity (P<0.05) and there was a tendency of less standing behavior (P=0.08) when compared to the lambs in shorn group. The difference of the other behaviors was not significant (P>0.05). Within the observation hours, there was a tendency of difference for behavioral frequencies between groups especially early in the day and late at night (P=0.07). But during the day, the difference of behavior type between groups was highly significant at 1300 and 1600 hours (P<0.01 and P<0.001, respectively). The findings of the current study showed that the behavior of shorn lambs changed with the changing of environmental heat and showed more behavioral differences at 1300 hours but they tend to cope with heat stress better than unshorn lambs in a hot environment when their rectal temperatures were compared.