Influence of environmental enrichment on aggressive behaviour and dominance relationships in growing pigs

Citation
Ne. O'Connell et Ve. Beattie, Influence of environmental enrichment on aggressive behaviour and dominance relationships in growing pigs, ANIM WELFAR, 8(3), 1999, pp. 269-279
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences
Journal title
ANIMAL WELFARE
ISSN journal
0962-7286 → ACNP
Volume
8
Issue
3
Year of publication
1999
Pages
269 - 279
Database
ISI
SICI code
0962-7286(199908)8:3<269:IOEEOA>2.0.ZU;2-#
Abstract
This study examined the effects of environmental enrichment on aggressive b ehaviour and dominance relationships in growing pigs. Three hundred and twe nty pigs were reared from birth to 15 weeks of age in either barren or enri ched environments. The barren environments were defined by common intensive housing conditions (ie with slatted floors and in terms of recommended spa ce allowances), while the enriched environments incorporated extra space an d substrates for manipulation. Aggressive behaviour was observed in a socia l confrontation test during the suckling period and dominance relationships were assessed from a food competition test at 12 weeks of age. Animals wer e weighed at regular intervals throughout the experiment. Environmental enr ichment reduced the expression of aggressive behaviour. Pigs from enriched rearing environments fought significantly less with unfamiliar animals than those from barren environments when tested under standard conditions (mean of 1.46 vs 2.75 fights per 30min test for enriched vs barren environments, SEM 0.20 P < 0.001). The nature of dominance relationships also appeared t o differ between barren and enriched environments. In barren environments, dominance among pen mates was correlated with (r = 0.33, P < 0.01), whereas in enriched environments it was correlated with body weight (r = 0.24, P < 0.01). Correlations between behaviour in the social confrontation and food competition tests suggested that dominance characteristics were establishe d early in life and remained stable through the growing period.