Behavioural comparison of transgenic and control sheep: movement order, behaviour on pasture and in covered pens

Abstract

AbstractBecause of the evidence that growth hormone gene transfer in pigs and mice can result in widespread pathological changes and more general concerns that transgenesis techniques themselves may have deleterious effects, a study was undertaken to compare the behaviour of two populations of immature female sheep, one of transgenic and one of control animals. The gene transferred was that for human alpha-1 antitrypsin factor. In the first part of the study the behaviour of 25 transgenic (T) and 25 control (C) sheep was compared in three separate situations: competition for a limited quantity of supplementary concentrate, six categories of normal behaviour on pasture and movement order when driven through a crush. With two minor exceptions (idling and ‘other’ behaviour in focally sampled animals), none of the differences observed between the two populations was significant and in most cases the mean values observed for T and C sheep were very similar. In the second part 25 T and 25 C sheep (different individuals from those in part 1) were compared in straw-littered covered pens for both normal behaviour and competition for a complete diet provided in a trough. The only significant differences in the seven categories of normal behaviour were a lower incidence of idling and ‘other’ behaviour in T sheep. There was a difference between T and C sheep in their social interaction under very competitive conditions (the T sheep reached food less quickly). The behavioural differences found in this study were all slight. Overall, the findings suggest that the gene transferred had no detectable deleterious effects on the normal behaviour of immature animals.