Interspecific differences in sociability, social novelty preference, anxiety- and depression-like behaviors between Brandt's voles and C57BL/6J mice

The three-chamber test has been widely used to investigate social approach/novelty preference in rodents. Most studies have used the briefly familiar and unfamiliar individuals as stimuli to examine social recognition; however, little is known about the effects of long-term familiar peers in this paradigm. In the present study, we made a slight modification to it: the first phase measured preference for a cage-mate (not a novel individual) over an identical wire cage without an individual stimulus; the later phase measured preference for a novel individual placed in the previous empty wire cage compared to the cage-mate (not the briefly familiar individual). The present study aimed to compare differences in sociability and social recognition between Brandt's voles (Lasiopodomys brandtii) and C57BL/6J mice using this modified three-chamber test. The levels of anxiety-, depression-, and anhedonia-like behaviors were also examined in both species. We found that Brandt's voles preferred the cage-mate over the empty cage in phase 1 and showed a preference for the novel individual in phase 2. In C57BL/6J mice, males showed no preference for familiar peers in phase 1, whereas females failed to show a preference for the novel individual in phase 2, showing a sex-specific difference. Furthermore, Brandt's voles displayed higher levels of locomotor activity and sociability as well as lower levels of anxiety-, depression-, and anhedonia-like behaviors than C57BL/6J mice. Interestingly, sociability and social approach correlated with depression-like behavior, whereas social novelty preference correlated with anhedonia-like behavior. Together, these data indicate that Brandt's voles and C57BL/6J mice show significant differences in sociability, social recognition, and levels of anxiety- and depression-like behaviors. Furthermore, Brandt's voles are more suitable for the study of selective social relationships.