The normal activity of the albino rat from birth to natural death, its rate of growth and the duration of life

Abstract

Investigated the normal activity of the albino rat from birth to death due to old age, its rate of growth, and the duration of life. Eight offsprings (28 days old) of 2 female rats, having mated to the same male, were taken. Four were placed in revolving cages, and the remaining, used as controls, were placed in stationary cages. Results show that the daily activities of the rats increased rapidly during the 1st third of their life, after which there was a continuous decrease. The change in amount of daily activity was rhythmic in character. The character of activity during youth and old age was quite similar, and the nature of activity during youth was nocturnal. Female rats were more active than the male. The controls reached their maximum weight at an earlier age than the exercised ones and also excelled them. The exercised rats were more active, alert, brighter, and had a shorter life span than the controls. (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1912 American Psychological Association.