Effect of Group vs. Single Housing on Phenotypic Variance in C57BL/6J Mice

摘要: Objective: To determine if group housing affects the variance of body composition parameters in a highly inbred mouse strain. Research Methods and Procedures: Thirty 3-week-old male C57BL/6J mice were obtained from Jackson Laboratory. Fifteen housed individually, 15 groups 5/cage. Animals fed ad libitum maintained same room under 12:12-hour light/dark photoperiod at 22 °C for 9 weeks. killed, fat mass, soft-lean tissue bone mineral density (BMD), content (BMC) determined by DXA. At necropsy, weights paired epididymal pads, retroperitoneal right inguinal pad, liver, kidneys, testes, seminal vesicles obtained. Results: Relative to singly, group-housed showed significantly greater percentage fat, testes weight, BMC. Group-housed tended show liver BMD. Mice singly smaller, had less mass BMC, lower BMD when compared with mice. Discussion: These results suggest that respect parameters, are more similar one another than mice, most likely because reduction environmental (predominately behavioral/social) effects. Thus, may be representative genotypic effects on mice. Whether other strains responses condition is unknown.