Dietary protein content affects the response of meadow voles, Microtus pennsylvanicus, to over-marks

Abstract

The response to signals, including scent marks, from opposite-sex conspecifics can be affected by the nutritional state of both the sender and receiver of these signals. Protein content of the diet affects how meadow voles (Microtus pennsylvanicus) respond to single scent marks, but it is unknown how it affects an individual's response to the overlapping scent marks of two donors (an over-mark). In experiment 1, we tested the hypothesis that protein content of the diet affects the amount of time voles spend investigating the marks of the top-and bottom-scent donors of an over-mark. Males and females fed a 22% protein diet spent more time investigating the scent mark of the top-scent donor than that of the bottom-scent donor; voles fed 9% and 13% protein diets spent similar amounts of time investigating the top-and bottom-scent donors. In experiment 2, we tested the hypothesis that protein content of the diet of the top-and bottom-scent donors affects the amount of time conspecifics spend investigating their scent marks. Female voles spent more time investigating the mark of the top-scent male than that of the bottom-scent male, independent of the differences in protein content of the diets of the top-and bottom-scent donors. Male voles, however, spent more time investigating the top-scent female when she was fed a diet higher in protein content than that of the bottom-scent female. Our results are discussed within the context of the natural history of voles.

Sex‐specific variation in the onset of reproduction and reproductive trade‐offs in a boreal small mammal

“…In addition, pup growth can be affected by maternal dietary protein level (reviewed by Speakman 2008). For males, on the other hand, a high-protein diet has been shown to act as a competitive advantage, as female meadow voles consider scent marks of males on a high-protein diet most attractive (Ferkin et al 1997, Hobbs andFerkin 2011). Consequently, it was surprising that food quality had no detectable effect on maturation and reproduction in either female or male bank voles.…”

“…On the other hand, a protein content of 20% and above was found in preferable habitats, often near cultivated areas. Studies that used a similar manipulation of protein content showed that male meadow voles fed with high-protein diets are more attractive to females (Ferkin et al 1997), and further, dietary protein increases males' sexual signaling with scent marks (Hobbs and Ferkin 2011). Meadow voles are considered to be more herbivorous than bank voles (Butet and Delettre 2011), but for the most part their diets are very similar.…”

Odor Communication and Mate Choice in Rodents

“…Scent-marks provide honest signals of health and nutritional status of senders to receivers [ 42 , 43 , 44 ]. Thus, the attractiveness of an individual’s scent marks can vary according to the diet and the amount of food a sender consumes [ 36 , 45 , 46 , 47 ]. Similarly, the receiver’s nutritional state affects its response to the scent marks of opposite-sex conspecifics [ 48 , 49 ].…”

Female meadow voles, Microtus pennsylvanicus, do not alter their over-marking in response to female conspecifics that were food deprived

“…The fact that FD females do not lower their rates of scent marking and over-marking relative to those of AL females suggests that they are not sacrificing opportunities to solicit mates despite facing food deprivation (Hobbs and Ferkin 2011a). However, males voles respond preferentially to the scent marks of AL females compared to those of FD females (Pierce and Ferkin 2005; Pierce et al 2005; Hobbs and Ferkin 2011b). Thus, males may be less interested in seeking out a FD female and mating with her if he also encounters the scent mark of an AL female in the same area.…”