Rearing rats in a germ-free environment eliminates their odors of individuality

  title={Rearing rats in a germ-free environment eliminates their odors of individuality},
  author={Prim B. Singh and J Herbert and Bruce Joseph Roser and L Arnott and David K. Tucker and Richard E. Brown},
  journal={Journal of Chemical Ecology},
In order to test the hypothesis that commensal bacteria influence the urinary odors of individuality, we collected urine from PVG and PVG.R1 male rats born by cesarian section and reared in a germ-free environment. Using the habituation-dishabituation test with PVG.RT1u and Lister hooded rats as subjects, we found that urine from the germ-free rats was not discriminated, while urine from conventionally housed rats of the same strains could be discriminated (experiment 1). When the germ-free… 

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