正常家兎の體温水準の高さ・動き並びに氣温條件の役割に關する實驗的吟味

Abstract

Rectal temperatures of 705 rabbits were measured seven times a day under ordinary conditions. 4935 measurements obtained during three years and four months were analyzed with special reference to the environmental temperature ranging from 4°C to 31°C. The average body temperature was found 39°.40C, standard deviation being 0°.29C with normal frequency distribution. A normal level of body temperature of rabbits, in group averages, was proved to change with a certain correlation to its thermal surroundings. Daily variations, the lowest at noon and the highest in the evening throughout a year, formed a V-shaped curve and the span of the diurnal rhythm changed, with its thermal surroundings, indicating a highly unstable state of body, temperature in severe seasons. This disturbance was easily evoked in winter than in summer. A small fraction (7.6 %) of the whole data went beyond the stipulated limits (38°.9C to 39°.8C in J.P. and U.S.P.) and further analyses represented role of various external temperatures upon rabbits each temperature of the environment had its own significance in affecting the physiology of the animal. At a room temperature ranging between 17°, 28°C and 24°, 25°C, a thermal mechanism of. rabbit was most free from any restrictive influence from the outside. It was convinced that the stability of body temperature is retained on a practically constant level throughout the whole extent of this optimum range of the environmental temperature, i.e. 21°±4°C.