EFFECT OF TWO FORMS OF ENVIRONMENTAL ENRICHMENT ON A GROUP OF BLACKBUCKS (ANTILOPE CERVICAPRA) KEPT IN CAPTIVITY

There has been much scientific interest in environmental enrichment as a mean to improve the welfare of animals kept in captivity and to prevent stereotypies and other forms of abnormal behaviour. However, ungulates have been little studied in this respect in comparison with other species. The aim of this study was to evaluate the behavioural effects of the introduction of a tree-trunk with branches and two brushes as forms of environmental enrichment for a group of eight blackbucks (one adult male, one sub-adult male, two young males, three adult females, one young female) kept in captivity in an outdoor enclosure with shelters. The animals were observed for four hours a day (09:30-11:30 and 12:30-14:30), twice a week, for two weeks pre-enrichment and two weeks post-enrichment, using instantaneous scan sampling every minute. The observation took place between October and December 2011. Statistical analyses were performed using Wilcoxon test for paired data. When the enrichments were present, the animals were significantly (Z=2.38; p=0.017) more visible in the enclosure, were lying inactively less (Z=2.52; p=0.012), performed more self-grooming (Z=2.52; p=0.012), sniffed other animals less (Z=2.24; p=0.025), and were more often displaced by another animal (Z=2.11; p=0.035). The blackbucks also interacted with the tree-trunk significantly more than with the brushes (Z=2.37; p=0.018). It is concluded that a tree-trunk with branches could be a useful short- to medium- term enrichment for blackbucks in captivity.