RELATION OF CERTAIN ENDOCRINE GLANDS TO BODY WEIGHT IN GROWING AND MATURE GUINEA PIGS12

Abstract

IN ENDOCRINE studies involving the use of experimental animals, it is important to be able to differentiate between the normal weight changes of the several endocrine glands associated with increasing body weight and changes which may be due to experimental conditions. Even when a considerable number of control animals are included in an experiment, it is difficult to determine the influence of the experimental condition upon gland weight, if the experimental treatment also influences growth rate, unless controls of various body weights are autopsied. Under such conditions, standards of normal endocrine gland weight with increasing body weight should be valuable reference data for comparative purposes. Since gland weights in general do not vary directly (to the first power) with body weight, but to some other power of body weight, the power formula or the relative growth equation Y = aXb has been used widely in statistical studies relating organ weight to body weight (DuBois, 1898; Lapicque, 1898;