The behaviour of gestating dairy ewes under different space allowances

Abstract

Provision of adequate housing is essential to assure the welfare of farm animals. One relevant aspect is space allowance, due to potential consequences on the behaviour and welfare of animals. The objective of this study was to determine the effect of space allowance on the behaviour and potential welfare implications of dairy ewes during gestation. With this purpose, 54 pregnant ewes were randomly allocated to groups of 6 ewes with space allowances of 1, 2, or 3m2/ewe (three replicates per treatment). Behaviour was observed between gestation weeks 9 and 19. Data collection included focal observations (4 gestation periods of 2 consecutive weeks, 3 days/week) and scan samplings (twice/week during 11 gestation weeks). The effects of space allowance, point of gestation, and their interaction on the percentage of time, frequency (focal observations) and percentage of occurrence (scan samplings) of behaviours were determined with a mixed model ANOVA, with point of gestation as repeated measure. In general, less activity as indicated by reduced movement (P<0.05) and higher percentages of time at the feeder (P<0.05) were observed at 1m2/ewe as compared to 2 and 3m2/ewe. Occurrences of negative, and especially positive social interactions, were also higher at 1m2/ewe (P<0.05), perhaps as result of the higher chances to find another individual in the path of movement rather than of increased social conflict. The initial period of study was characterized by a higher frequency of positive social interactions (P<0.001) and explorative behaviours (P<0.005), likely due to the novelty effect. On the contrary, the decline in activity, as indicated by a reduction in the percentage of time standing (P<0.05) and increased resting (P<0.05), was evident as gestation progressed. A clear effect of space allowance was detected, although it was mostly restricted to moving and eating behaviours.