EXCHANGE OF PROTEINS AND NUCLEIC ACIDS IN THE TISSUES OF CHICKENS IN CONNECTION WITH AGE AND PHYSIOLOGICAL STATE OF THE BODY

Abstract

The results of the study of the exchange of proteins and nucleic acids in the tissues of chickens in connection with the age and physiological state of the body are given. It was established that the live weight of experimental chickens met their standards, which are accepted for the corresponding age periods. The fastest growth and development was observed in the first three months of life, then body weight increased more slowly, and at the age of 6.5-12 months it was maximum - 2000-2200 g for Leghorn chickens, 2200-2400 g - for New Hampshire chickens. The absolute weight of the liver of Leghorn chickens gradually increased until almost 12 months of age (spring egg-laying), and during molting and sexual rest (18 months) it significantly decreased (by 24%) and corresponded to the weight of the organ during puberty (4.5 months ). With the beginning of a new egg-laying cycle (20 months), the weight of the liver increased again, but did not reach the level of spring egg-laying (12 months). The relative weight of the liver gradually decreases with age, except for the weight during winter egg laying (6.5 months) and during spring egg laying (12 months). During these periods, the relative weight of the liver does not change. The absolute mass of both sections of the oviduct increases many times before the beginning of egg laying and reaches its maximum values during spring egg laying, exceeding by 4-8 times their mass during puberty (4.5 months), and with the cessation of egg laying it sharply decreases and reaches the level during puberty. With the beginning of a new egg-laying cycle, both sections of the oviduct increase again by 2-4 times, but do not reach their mass at the age of 12 months. In the liver, the content of non-

protein nitrogen also actively increases with age, and its maximum values are noted at 6.5 and 12 months, that is, at the beginning and during the most intensive spring egg-laying, and during the period of sexual rest, its amount decreases by 20- 25%; with the beginning of the second ovulation cycle, a new rise is noted, but to a lesser extent than in previous periods of sexual activity.