Basal Metabolism of the Adult Rabbit and Prerequisites for Its Measurement

Abstract

For basal metabolism measurements on normal adult rabbits, animals in good nutritive state with rectal temperatures between 38.4° and 41.1°C. should be used. The measurements can be made at any time of day or night. Absence of muscular activity is necessary. The rabbits should have fasted for from 24 to 72 hours prior to measurement, should have been living at environmental temperatures above 20° but not above 32°, and should have been habituated to the environment of thermic neutrality (28° to 32°C.) for 24 hours or longer prior to the observations at thermic neutrality. The initial experiment on any rabbit not previously accustomed to laboratory procedures should be considered only as an orientation experiment. The rabbit's basal metabolism was established by 251 experiments on seventy-four adult animals, ranging in weight from 1 to 7 kg. The total heat production ranged from 60 to 335 calories per 24 hours and the heat production per square meter of surface area from 534 to 914 calories, being in general higher the heavier the weight. The males tended to have a slightly higher metabolism than the females. There was no pronounced correlation between rectal temperature and heat production. The heat values per square meter were lower than most of the values reported in the literature, probably because of strict adherence to basal conditions of measurement.