Annual variation of water content and energy value of the major energy reserves in adult lizards (Eremias brenchleyi)

摘要

Annual variation of water content and energy value of the major energy reserves were studied in adult lizard, Eremias brenchleyi , from a population in Suzhou, Anhui, eastern China. Monthly samples of the adult lizards were collected during September to November 2001 and March to August 2002. The lizards were brought to our laboratory in Chuzhou Normal College. The lizards were killed by freezing to -15℃, and then separated into carcasses (including tails), livers and abdominal fat bodies. The three components were oven dried to constant mass at 65℃, weighed and preserved frozen for later determination of composition. We extracted non polar lipids from dried samples (except abdominal fat bodies) in a Soxhlet apparatus for a minimum of 5.5 h using absolute ether as solvent. The amount of lipids in a simple was determined by subtracting the lipid free dry mass from total sample dry mass. We determined energy value of dried samples including carcasses, livers, abdominal fat bodies and non polar lipids using an adiabatic bomb calorimeter. Males and females differed in water contents of carcass and liver. Water contents of carcass and liver were all higher in males than in females. There were significant monthly changes in water contents and energy values of carcass (including lean carcass) and liver in both males and females. Significant monthly changes in energy values of abdominal fat bodies were also found in both sexes. Energy values of carcass (including lean carcass) and liver were higher in males than in females, but those of liver lower in males than in females. Our results indicated that annual variations in the major energy reserves were correlated with the reproduction and winter hibernation. Proper energy storage in breeding season of male would be help for to strengthen the ability of quick movement, while, that of female would be increase reproductive output and improve survival and fitness［ Acta Zoologica Sinica 49(2):191-197,2003］.