High-throughput, ecologically-relevant assessment of social hierarchy in group-housed mice.

Measuring complex social phenomena such as hierarchy can be challenging under laboratory conditions. Typical assessment methods focus on aggressive or stress-related behaviors, which are not very prevalent in the wild, where rodents form  stable groups of well-defined social order. In the presented work we examine spontaneously-formed social structure  in group-housed mice under sumi-naturalistic conditions.

We show that social dominance, measured as  time spent on consumption of highly motivating, yet spatially limited reward can easily be assessed in Eco-HAB and thus we are able to describe the spontaneously-forming social structure of any given cohort of mice.

Additionally, analysis performed on behaviors of individual mice allowed us to discover that each animal has a unique pattern of social interactions with cohort-members that is stable over many days, even after we introduced a limited rewarding resource.

These results show that social hierarchy and complex group dynamics of mice can be measured in ecologically valid behavioral assays such as Eco-HAB. Further, utilizing a spatially limited reward paradigm enables us to perform experiments on social dominance in a stress minimizing manner, without interference with spontaneously-formed social structure.