[A feeding experiment on laboratory-bred male cynomolgus monkeys. I. Morphometrical study]

Effects of restricted feeding on the growth of laboratory-bred male cynomolgus monkeys (Macaca fascicularis) aged between one year and four years were studied morphometrically. A series of 11 variables representing physical elements were measured. Before 2.5 years of age, the amount of commercial diet (Type AS, 382kcal/100g and 28.1% of crude protein, Oriental Yeast Co. Ltd.) per day was restricted to 50g (group A), 30g (group B) or 20g (group C) and increased to 100g (group A), 50g (group B) or 40g (group C) respectively at 2.5 years old. Throughout the experimental period ca 100g of apples and oranges per day were provided. Significant differences in body weight between group A and C were detected excepting the early period of the experiment. Although the slight suppression in weight gain was observed in group B during the second trimester of the experiment, body weight increased gradually after increasing the amount of food and no significant difference from A was observed at four years of age. The minimum requirement of diets is judged to be 30g/day before two years old and 50g/day over two years old in the laboratory-bred male cynomolgus monkey. Moreover, the suppressive effects of restricted feeding were most significant on the growth of the limbs and, secondarily, on the growth of the trunk. Practically no effect on the growth of the head was observed.