Nonsocially housed rats (Ratus norvegicus) seek social interactions and social novelty more than socially housed counterparts.

Abstract

Sociability is the act or quality of social interaction and can be quantified by determining the number and duration of interactions with conspecifics. The purpose of this study was to examine the extent to which sustained social contact, as achieved by constant social living conditions, influenced social behavior. Beginning in juvenility, 19 male Long-Evans rats were housed in enriched environments, with half living socially in a large group and half living individually. After several months in these housing conditions, rats were tested on a sociality test and a social novelty preference test. Nonsocially housed rats exhibited more social behavior than socially housed rats. In the sociality test, nonsocially housed rats engaged with an unfamiliar rat more than socially housed rats. Similarly, in the social novelty test, nonsocially housed rats visited a novel stranger more than the now-familiar rat (from the sociality test) as compared with the socially housed rats. It is unlikely that general anxiety factors can account for between-groups social effects, as there were no group differences in behavior on the elevated zero maze and open field test. Furthermore, socially and nonsocially housed rats were matched in spontaneous object exploration and novelty preference in a novel object recognition test, eliminating the possibility that general exploratory behavior or novelty preference accounted for group differences in the sociability tasks. These results suggest that lack of social interaction in nonsocially housed rats may be more powerful for social motivation than the consistent opportunity for social contact afforded by social living conditions. (PsycINFO Database Record

Social preference in rats

“…Previous research has supported a distinction between appetitive (social approach) and consummatory (social contact and engagement) aspects of social interaction, finding that these two components of socially motivated behavior respond differentially to neuroanatomical (Diergaarde et al, 2005) and environmental (social housing) (Templer et al, 2018) manipulations. The present study focused on what would be considered appetitive (tendency to work for and approach opportunities for social interaction) rather than consummatory (the social interaction itself).…”

Playback of Alarm and Appetitive Calls Differentially Impacts Vocal, Heart-Rate, and Motor Response in Rats

“…In addition, the single rats spent more time in the speaker's half of the cage during playback sessions than the paired rats ( Figures 4 A, 4C, and 4E; Tables S10 and S13 B), an equivalent of approach behavior described before ( Wohr and Schwarting, 2007 ). It was demonstrated that nonsocially housed male rats are more sociable and have higher social novelty preferences than socially housed counterparts ( Templer et al., 2018 ). Therefore, our single rats were old enough, with alleviated stress levels and socially motivated to demonstrate increased locomotor activity and approach behavior, higher HR, and more ultrasonic emissions in response to playback compared with the paired rats.…”

Impaired social behaviour and molecular mediators of associated neural circuits during chronic Toxoplasma gondii infection in female mice

“…Interestingly, several studies have highlighted that long-term socially isolated rodents fail to show a robust social interaction induced c-Fos production (Ieraci et al, 2016;Lukkes et al, 2012;Wall, 2012). In contrast, it has also been shown that isolation-housed rats approached a novel conspecific more than group-housed rats, and isolation acted as a strong motivator to social approach (Templer et al, 2018;Wall, 2012). Indeed, a 3 week isolation period did not impair c-Fos induction upon social intersection (Avale et al, 2011).…”