Physiology & Behavior, Vol. 67, No. 2, pp. 243–248, 1999 © 1999 Elsevier Science Inc. Printed in the USA. All rights reserved 0031-9384/99/$–see front matter PII S0031-9384(99)00066-9 243 Effects of Food Deprivation and Metabolic Fuel Utilization on Food Hoarding by Jirds (Meriones shawi) GREGORY E. DEMAS AND TIMOTHY J. BARTNESS 1 Department of Biology, Neurobiology Program Georgia State University, University Plaza, Atlanta, GA 30303 Received 2 November 1998; Accepted 16 March 1999 DEMAS, G. E. AND T. J. BARTNESS. Effects of food deprivation and metabolic fuel utilization on food hoarding by jirds (Meriones shawi). PHYSIOL BEHAV 67(2) 243–248, 1999.—Food hoarding plays an important role in the energetic repertoire of a variety of mammalian species. Both food hoarding and food intake have been examined in rodents using sev- eral energetic challenges including food deprivation, treatment with metabolic fuel blockers, and enhancement of fuel stor- age. In the present experiment, we examined food hoarding by female jirds (Meriones shawi), a desert rodent species occupy- ing the arid steppes and desert regions of Egypt. Jirds are prodigious hoarders in the field; however, virtually nothing is known about their hoarding within controlled laboratory settings. In the present study, the effects of food deprivation as well as alterations in metabolic fuel utilization (i.e., 2-deoxy-D-glucose and isophane insulin) on food hoarding and food intake were tested in female jirds using a simulated burrow system. Jirds decreased body mass and increased food consumption fol- lowing either 32 or 56-h food deprivation. Food hoarding, however, was virtually abolished after food deprivation and treat- ment with 2-DG. In contrast, isophane insulin treatment had no effect on food consumption or hoarding in this species. Taken together, the present results suggest that total body mass (fat), rather than short-term metabolic fuel utilization, regu- lates both food consumption and hoarding in female jirds. In addition, these results provide a novel set of appetitive re- sponses to these energetic challenges in small mammals. © 1999 Elsevier Science Inc. Energetics Desert rodents Metabolic fuels Food intake 2-DG Insulin ANIMALS require a balanced energy budget (i.e., energy in- take must be equal or greater than energy expended) in order to survive and reproduce. To accomplish this goal, animals must maintain a relatively constant flow of energy input de- spite fluctuating energy supplies and demand (28). Energetic deficits can be overcome by small mammals through either decreases in energy expenditure (e.g., reducing metabolic rate) or increases in energy intake (e.g., increasing body fat stores). Another way by which energy demands can be met is through food hoarding. During times of high food availability, food can be collected and stored externally in the form of a cache; this cache can be consumed later during times of food scarcity (7,26,27). A wide range of rodent species exhibit food hoarding un- der both field and laboratory conditions. For example, food hoarding occurs among Mongolian gerbils (Meriones unguicu- latus), laboratory rats (Rattus norvegicus), white-footed mice (Peromyscus leucopus), deer mice (Peromyscus maniculatus), as well as both Syrian (Mesocricetus auratus) and Siberian (Phodopus sungorus) hamsters [reviewed in (27)]. Despite the ubiquity of food hoarding, very little is known regarding the underlying physiological mechanisms controlling food hoarding. As for food intake, however, the onset and offset of food hoarding is assumed to be “regulated”(17). For example, conditions that reduce body mass (primarily in the form of a loss of body fat) increase food hoarding in several species (2,8). Both food deprivation and chronic food restriction in- creases food hoarding in laboratory rats (8), and Syrian (25,29), and Siberian hamsters (2). Beyond these relatively superficial relations, the mechanisms underlying food hoard- ing are largely unknown in any species. Despite considerable data on food hoarding in commonly studied laboratory species, such as rats and hamsters, very lit- tle is known about hoarding in other less domesticated spe- 1 To whom requests for reprints should be addressed. E-mail: bartness©gsu.edu