Mate choice voles

Meadow vole Anal gland, urine, feces Protein, 9,15 or 25% Mate choice voles with high-protein diet preferred... 

Shapiro, L.E., Austin, D., Ward, S.E. and Dewsbury, D.A. (1986) Familiarity and female mate choic ein two species of voles (Microtus ochrogaster and Microtus montanus). Anim. Behav. 34, 90-97. 

Wolff, J. O., Watson, M.H., and Thomas, S.A. (2002) Is self-grooming by male prairie voles a predictor of mate choice Ethology 108, 169-179. 

In some mate choice studies, urine is presented in place of the whole animal in order to demonstrate that odours are, or can be, mediators of disassortative mating (e.g. Ninomiya and Brown, 1995 Ehman and Scott, 2001). In the absence of more direct measures, such as asking human subjects which odour they prefer (e.g. Wedekind et al., 1995), the duration of investigation or time spent near an odour are generally assumed to equate directly to preference. This can be misleading when the assumption is not explicitly tested. For instance, female voles have been shown to exhibit an odour preference for unparasitized males which does not correlate with mate selection (Klein et al., 1999). 

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