Mice living in social hierarchies express different levels of oxytocin receptor (OTR) and vasopressin 1a receptor (V1aR) binding in various brain regions according to their social status.• Alphas and subdominants have higher OTR binding in the nucleus accumbens compared to subordinates.• Alphas have higher OTR binding in the anterior olfactory nucleus compared to subdominants and subordinates.• Alphas have higher OTR and lower V1aR binding in the rostral lateral septum compared to subordinates.• Alphas have lower V1aR binding in the lateral preoptic area compared to subordinates..

Living in social hierarchies requires individuals to adapt their behavior and physiology. We have previously shown that male mice living in groups of 12 form linear and stable hierarchies with alpha males producing the highest daily level of major urinary proteins and urine. These findings suggest that maintaining alpha status in a social group requires higher food and water intake to generate energetic resources and produce more urine. To investigate whether social status affects eating and drinking behaviors, we measured the frequency of these behaviors in each individual mouse living in a social hierarchy with non-stop video recording for 24 h following the initiation of group housing and after social ranks were stabilized. We show alpha males eat and drink most frequently among all individuals in the hierarchy and had reduced quiescence of foraging both at the start of social housing and after hierarchies were established. Subdominants displayed a similar pattern of behavior following hierarchy formation relative to subordinates. The association strength of foraging behavior was negatively associated with that of agonistic behavior corrected for gregariousness (HWIG), suggesting animals modify foraging behavior to avoid others they engaged with aggressively. Overall, this study provides evidence that animals with different social status adapt their eating and drinking behaviors according to their physiological needs and current social environment.

Competent social functioning of group-living species relies on the ability of individuals to detect and utilize conspecific social cues to guide behavior. Previous studies have identified numerous brain regions involved in processing these external cues, collectively referred to as the Social Decision-Making Network. However, how the brain encodes social information with respect to an individual’s social status has not been thoroughly examined. In mice, cues about an individual’s identity, including social status, are conveyed through urinary proteins. In this study, we assessed the neural cFos immunoreactivity in dominant and subordinate male mice exposed to familiar and unfamiliar dominant and subordinate male urine. The posteroventral medial amygdala was the only brain region that responded exclusively to dominant compared to subordinate male urine. In all other brain regions, including the VMH, PMv, and vlPAG, activity is modulated by a combination of odor familiarity and the social status of both the urine donor and the subject receiving the cue. We show that dominant subjects exhibit robust differential activity across different types of cues compared to subordinate subjects, suggesting that individuals perceive social cues differently depending on social experience. These data inform further investigation of neurobiological mechanisms underlying social-status related brain differences and behavior.

Living in social hierarchies requires individuals to adapt their behavior and physiology. We have previously shown that male mice living in groups of 12 form linear and stable hierarchies with alpha males producing the highest daily level of major urinary proteins and urine. These findings suggest that maintaining alpha status in a social group requires higher food and water intake to generate energetic resources and produce more urine. To investigate whether social status affects eating and drinking behaviors, we measured the frequency of these behaviors in each individual mouse living in a social hierarchy with non-stop video recording for 24 hours following the initiation of group housing and after social ranks were stabilized. We show alpha males eat and drink most frequently among all individuals in the hierarchy and had reduced quiescence of foraging both at the start of social housing and after hierarchies were established. Subdominants displayed a similar pattern of behavior following hierarchy formation relative to subordinates. The association strength of foraging behavior was negatively associated with that of agonistic behavior corrected for gregariousness (HWIG), suggesting animals modify foraging behavior to avoid others they engaged with aggressively. Overall, this study provides evidence that animals with different social status adapt their eating and drinking behaviors according to their physiological needs and current social environment.

Competent social functioning of group-living species relies on the ability of individuals to detect and utilize conspecific social cues to guide behavior. In many species, cues about an individual's identity, including social status, are conveyed through urinary proteins. Previous studies have identified numerous brain regions involved in processing these external cues, collectively referred to as the Social Decision-Making Network. However, how the brain encodes social information with respect to an individual's internal social status has not been thoroughly examined. Here we show that neuronal activity in male mice, as indicated by cFos immunoreactivity, is modulated by the social status and familiarity of the cue source and the subject's own social status. The posteroventral medial amygdala was the only brain region that responded exclusively to the social status of the cue source. Activity in other brain regions was modulated by social status. Specifically, within the brain of dominant subjects there was robust differential activity dependent on the status or familiarity of the cue source. Our results suggest that individuals perceive social cues differently depending on their social experience. These data inform further the investigation of neurobiological mechanisms underlying social-status related brain differences and how social status-associated differences influence physiology and behavior.