[Quantity of foods, weight of anatomic structures and body weight in the muskrat (Ondatra zibethicus, L., 1766)].

Weights of skeletons, several viscera (heart, lungs, empty stomach and intestine, liver, spleen, kidneys) and muscles of 80 muskrats were taken. The data were analyzed and compared versus four classes of ages and sexes: adult males, adult females, sub-adult males and sub-adult females. The weight of the muscles is 47 to 50% of the live-weight in the four classes studied. The weight of the viscera is approximately 10 to 12% of the live-weight. Thus, the weight of edible matters varies, in the muskrat between 57 and 62% of the live-weight. The spleen of adult females is relatively heavier than that of adult males or sub-adult females.