Changes in the nucleic acid and protein content of the Japanese quail during postnatal development.

A study of growth activity in the Japanese quail showed the rate of growth to be the highest, in both sexes, between the ages of 5 and 20 days. Positive allometry was manifested in skeletal muscle development, negative allometry or isometry in the case of the liver and heart. The protein/P DNA ratio rose progressively with age in all the given tissues and attained the maximum prior to sexual maturation. The P RNA/P DNA ratio rose markedly in all the tissues after only a few days and remained high throughout the whole period of development. Growth dynamics in the both sexes followed the same course; the only exception were proteosynthesis indicators, which attained higher values in females, in correlation to their greater body weight.