Seasonal changes in caloric value, body water and fat in some shrews

Abstract

Abstract The caloric equivalent of the body dry mass and biomass of the shrew (Sorex araneus, S.ﾂminutus, and Neomys fodiens) shows statistically significant changes in the annual cycle and is higher in winter and early spring than in summer and early autumn. For ecological purposes it is suggested to use various caloric values of the shrew biomass in relation to the period of studies. The caloric value of 1ﾂg of biomass of Soricidae depends mainly on the degree of hydration of their tissues and is independent of changes in the body fat content. The amount of water in the shrew body is subjected to high, statistically significant variations in the annual cycle. Both the winter depression and spring rise in the body weight of these mammals are result mainly from changes in the tissue hydration. The fat content in the body of Soricidae is smaller than in rodents. Fluctuations in the amount of fat are result from the accumulation and utilization of the energy reserves present in BAT. All the studied indices showed no statistically significant differences related to the sex of animals.