Dynamics and rate of body temperature growth in hibernators upon awakening

The presented report analyzes the dynamics of body temperature and the rate of temperature growth during awakenings in winter-sleeping Sciuridae and Erinaceus families. Observations of body temperature were carried out with thermographs implanted in the body cavity. Analysis of the awakening showed that there is an S-shape of the temperature graph of self-heating. The rate of increase in body temperature in animals varies at different stages of self-heating. At the initial stage, the body temperature increases slowly and almost linearly. Then comes the phase of rapid growth of body temperature, which in all animals occurs in the range from 10-12 to 22-25ºС. The rate of temperature growth reaches a maximum, after which it sharply decreases. In the representatives of the five species under consideration, the peak rate of increase in body temperature was on average 0.2-0.35 deg/min. The average rate of temperature growth was 0.1-0.15 deg/min. In the white-breasted hedgehog E. roumanicus, the maximum rate is 60% higher than that of similar squirrels (S. undulatus, S. parryii and M. camtschatica) and is similar to the maximum heating rate of the chipmunk (T. sibiricus) with a body weight of an order of magnitude less.