Effects of food deprivation and metabolic fuel utilization on food hoarding by jirds (Meriones shawi)

Food hoarding plays an important role in the energetic repertoire of a vari ety of mammalian species. Both food hoarding and food intake have been exam ined in rodents using several energetic challenges including food deprivati on, treatment with metabolic fuel blockers, and enhancement of fuel storage . In the present experiment, we examined food hoarding by female jirds (Mer iones shawl), a desert rodent species occupying the arid steppes and desert regions of Egypt. Jirds are prodigious hoarders in the field; however, vir tually nothing is known about their hoarding within controlled laboratory s ettings. In the present study, the effects of food deprivation as well as a lterations in metabolic fuel utilization (i.e., 2-deoxy-D-glucose and isoph ane insulin) on food hoarding and food intake were tested in female jirds u sing a simulated burrow system. Jirds decreased body mass and increased foo d consumption following either 32 or 56-h food deprivation. Food hoarding, however, was virtually abolished after food deprivation and treatment with 2-DG. In contrast, isophane insulin treatment had no effect on food consump tion or hoarding in this species. Taken together, the present results sugge st that total body mass (fat), rather than short-term metabolic fuel utiliz ation, regulates both food consumption and hoarding in female jirds. In add ition, these results provide a novel set of appetitive responses to these e nergetic challenges in small mammals. (C) 1999 Elsevier Science Inc.