Effect of grouping time and group stability on behavior and aggression among rabbit does in a part-time housing system

To evaluate aggression and behaviour of reproducing does in a part-time system, 48 crossbred multiparous rabbit does were housed in individual modules of a park system. A total of 12 parks with 4 does were formed by joining adjacent modules from 9 d before kindling until 2 d before kindling and from 2 d or 12 d after kindling (early or late grouping time, respectively) until weaning. Within grouping time, half of the parks maintained a stable group; the other half changed one doe every week. Behaviour in all parks was videorecorded for 24 h at 2 d, 12 d and 19 d after kindling. The number of total aggressive interactions significantly decreased from the grouping day to the 19th d of lactation (P<0.001), and was lower in late grouped does compared to early-grouped ones (P<0.01) and in stable groups compared to variable groups (0.001<0.01). Regarding the time spent resting, feeding, drinking and self-grooming, the observation day always had a significant effect, whereas the group stability was less relevant. Finally, at 19 d, on average, does rested individually for a 45.3% of the observation time and in contact with a mate for a 17.2% of the observation time, without significant differences according to the grouping time or the group stability (P>0.05).