Bill, J., Rauterberg, S. L., Herbrandt, S. et al. 2020. Agonistic behavior and social hierarchy in female domestic rabbits kept in semi-groups. Journal of Veterinary Behavior 38, 21-31.

In semi-natural mixed-sex groups, rabbits (Oryctolagus cuniculus) organize their social life by forming a hierarchy, which is characterized by linearity and stability. Compared to the natural environment, many factors are different in contemporary breeding systems, such as space allowance and, in the case of semi-group housing, a period of single housing around parturition. Aggressive interactions and the resulting injuries are frequently regarded as negative. However, there is not much information about the social dominance among does in these breeding groups. Therefore, the aim of this study was to generate knowledge about the hierarchy in female rabbits kept in “semi-groups” on farms by using sociometric measurements. Sixteen semi-grouped does of three or five rabbits each with various degrees of familiarity were first mixed one week before parturition. After a separation period of either two or three weeks for giving birth, they were remixed with the same group mates. Both mixing procedures were video-analyzed for agonistic interactions. The observed agonistic behavior was mainly characterized by one-sidedness. Mixing rabbits before parturition did not prevent aggression after the separation period. The resulting hierarchies were neither found to be totally despotic nor egalitarian, as linearity was revealed in most groups, but steepness levels varied between them. While dominant does turned out to be rather despotic, showing high win proportions, the other relationships among lower-ranked does were more balanced. In contrast to the stable hierarchical structure in natural breeding colonies, rank order stability was not confirmed in the studied semi-groups. A larger group size negatively influenced the rank stability. Our results point out some characteristics of the social life in semi-grouped rabbit does in contemporary breeding systems and the differences to semi-natural habitats.