Secondary plant compound and photoperiod influences on the reproduction of two southern African rodent species, Gerbillurus paeba and Saccostomus campestris

Little information is available on the controls of reproduction in southern African small mammals. It was hypothesised that the unpredictable climate of the region would reduce the efficacy of photoperiod as a cue relative to that in temperate northern hemisphere species, and that secondary plant compounds would provide additional useful signals. The effects of short day photoperiod and feeding of the secondary plant compound, p coumaric acid (pCA), were tested in two widely distributed, seasonally breeding and sympatric species, the hairy footed gerbil (Gerbillurus paeba) and the pouched mouse (Saccostomus campestris). In neither species did either short day photoperiod or pCA significantly affect uterine or ovarian mass and follicular development. It was concluded that reproduction in these species is either cued by a combination of integrated signals or is controlled directly by energetic and metabolic constraints.