Inhibitors of carbohydrate metabolism reduce undirected song production at doses that do not alter food intake in singly housed male zebra finches

Previous findings in our laboratory indicate that food availability and/or the balance of metabolic fuels may play a role in the production of undirected song in singly housed adult male zebra finches (Taeniopygia guttata). In this study, 2-deoxyglucose (2-DG) or 2,5-anhydro-d-mannitol (2,5-AM) were used to attenuate the circadian shift from lipid to carbohydrate metabolism, which normally occurs at the onset of the light phase in free-feeding, singly housed zebra finches, in order to evaluate the possibility that carbohydrate metabolism influences the production of undirected song. Food intake was also measured. Both drugs (which block carbohydrate metabolism and increase reliance on lipid metabolism) produced dose-dependent reductions in undirected singing, while food intake was not altered. Our results suggest that undirected singing (and possibly other voluntary and/or social behaviors) is sensitive to the availability of dietary fuels, whereas, food intake may show a greater regulation by the availability of stored fuels.