Meeting Abstract
S10.10 Friday, Jan. 7 Ethanol Increase Food Consumption in summer but not in winter: Effects of Ethanol Consumption on Skin Temperature of the Egyptian Fruit Bats KORINE, Carmi*; SáNCHEZ, Francisco; PINSHOW, Berry; Ben-Gurion University of the Negev; Ben-Gurion University of the Negev, Universidad de Ciencias Aplicadas y Ambientales, UDCA; Ben-Gurion University of the Negev ckorine@bgu.ac.il
Yeasts are present in fleshy fruits whose sugars they use as a substrate for fermentation. As fruit ripens, the concentration of sugar increases, as does the concentration of the alcoholic products of fermentation of which ethanol is predominant. Since mammalian frugivores generally chose ripe fruit, they encounter ethanol that occurs in a particular range of concentrations. Ethanol at these concentrations may have positive or negative effects. We studied the role of ethanol as an appetitive stimulant and its effects on skin body temperature (Tbs)in Egyptian fruit bat, Rousettus aegyptiacus during winter and summer when in the latter fruit availability and quality is high and the costs for thermoregulation are low. During summer, food consumption of an artificial liquid food containing low concentrations of ethanol (0.01% and 0.5%) did not differ significantly from consumption of the control diet, but increased significantly at 0.1%, and at higher ethanol concentrations (1% and 2 %) food consumption decreased significantly. During winter, food consumption at all concentrations decreased significantly. Tbs decreased significantly at 12°C after ingesting liquid food that contained 1% ethanol, while it did not change in most of the bats fed with liquid food contained 0 % ethanol at 12°C or in bats that were fed with food contained 1% or 0% ethanol at 24°C. Our data indicate that ethanol may act as an appetitive stimulant on Egyptian fruit bats at low concentrations, but only during summer. Also, as long as bats have good body condition, they are probably more strongly deterred by ethanol-rich fruit during winter than in summer due to the hypothermic effects of ethanol.