Auto- and allo-grooming in pine voles (Microtus pinetorum) and meadow voles (Microtus pennsylvanicus)

Grooming was observed in mixed-sex pairs of voles after one vole had been unilaterally soiled with a carboxymethylcellulose (CMC) gel. In Experiment 1, soiled pine voles spent more time grooming than did clean voles, and groomed the soiled side of their bodies more than the clean side. Soiled voles of both species head-groomed more than did clean voles. Addition of tastants to CMC gel did not alter grooming durations in either species, and there were no sex differences. In Experiment 2, both vole species (taken together) auto-groomed more than they allo-groomed, although clean voles groomed their soiled partners more than themselves. These studies suggest that soiled fur is a powerful stimulus for auto- and allo-grooming.