Effects of amylin and salmon calcitonin on feeding and drinking behavior in pygmy goats

Abstract

In the present study, the effects of peripherally administered amylin and of the amylin-related peptide salmon calcitonin (sCT) on food and water intake was tested for the first time in pygmy goats. In the first series of experiments, the effect of amylin on food (0.5, 1.0 and 2.0 microg/kg b.wt.) and water (2.0 microg/kg) intake was tested. In the second series of experiments, the effect of sCT on food intake (1.0 microg/kg) was tested under ad libitum feeding conditions or after 14 h food deprivation. The relationship of dose on the effect of sCT (0.1, 0.5 and 1.0 microg/kg) on food and water intake was also tested. Finally, the effect of a low dose (0.1 sCT microg/kg) on water intake was also investigated during food withdrawal. We showed for the first time an anorexigenic effect of the satiety peptide amylin (2.0 microg/kg) in ruminants, which was characterized by a reduction in meal size. In pygmy goats, the administration of the three doses of sCT induced an anorexigenic effect, which was larger and of longer duration when compared with amylin, although the anorexigenic effect of the lowest dose never reached significance. This effect was not dose dependent and was partly due to a reduction in meal size and partly to a prolongation of the interval between meals. The anorexigenic effect of sCT was accompanied by a reduced water intake, probably due to reduced prandial drinking. Furthermore, the low dose of sCT (0.1 microg/kg) was dipsogenic during food withdrawal.