Characterization study of aggressive behaviours in group-housed rabbit does

A total of 32 crossbred multiparous pregnant rabbit does were housed in individual modules (0.5 m2) which were put in communication to form 8 double and 4 quadruple pens and to house 2 and 4 does, respectively. The females were maintained in stable groups from the starting of the trial (8 d before kindling) until 2 d before kindling and from the 18th day of lactation until weaning (31th day). The aggressive interactions among does were controlled by video-recording for 24 consecutive hours during the initial group formation at 8 d before kindling (−8 d), during the re-introduction in the groups at 18 d of lactation (+18 d) and at 21 and 30 d of lactation. At −8 d and +18 d group formations, the most observed aggressions were biting and attacking, followed by threatening, boxing and carousel fights, and finally chasing. There was a higher number of biting, threatening and total aggressions at −8 d than at +18 d (P<0.05). The effect of the observation hour was significant for all types of aggressive interactions (P<0.05) at both observation days, although with a different pattern for each day: at −8 d aggressions took place essentially during the first two hours after the group formation and thereafter they were reduced; at +18 d, the aggressions were concentrated on the first 30 minutes after the group formationand thereafter they were rather null. At 21 and 30 d of lactation, few and null aggressive interactions were observed, respectively. In conclusions, more aggressions and, likely, longer periods for establishing hierarchy were observed on the first group formation and with does close to the kindling, while lower aggressions and shorter periods for stabilisation were measured at the re-introduction in group and at the end of the lactation period.