In roosters, in the first three days after the removal of the gonads, the body temperature increased by 1,03-1,15º C compared with the control of the absence of a difference in pulse rates and the number of respiratory movements, which may be associated with surgical intervention. In the subsequent periods of the experiment, the body temperature, pulse and number of respiratory movements in the roosters of the experimental group were within their clinical values for a healthy bird. After the removal of the gonads, wound healing in the roosters of the experimental group occurred on the 3rd-4th day without any change in the clinical condition. Out of 20 roosters operated on using the improved testes removal technique, only one individual died on the first day after gonadectomy. In gonadoectomized roosters, the live weight on day 125 is 4,8% higher, while on days 65, 75, 85 and 95 this indicator did not actually differ from the control, and on days 105 and 115 it only had a tendency to increase. It was found that the weight of the gutted carcass of the experimental group after slaughter was 5,2 % higher, and the weight of the muscular part of the stomach was 7,8 % higher, while the weight of the semi-carcass carcass, the weight of the liver and heart did not differ from the control. The effect of gonadectomy on
the morphological composition of the blood of roosters on the 125th day of the experiment was revealed. The concentration of hemoglobin in the blood of the roosters of the experimental group was 9,8 % lower, the number of erythrocytes decreased by 18,7 %, leukocytes - by 19,7 %, platelets - by 30,7 %, and the erythrocyte sedimentation rate increased by 1,9 times compared to control. The
content of uric acid in the blood plasma of birds was 23,7 % higher in gonadectomized roosters compared to the control. The concentration of hemoglobin, the number of erythrocytes, leukocytes and the ratio of cells characterizing the leukogram in the roosters of the experimental group to gonadectomy did not change in accordance with the control, except for the number of platelets, which decreased by 11,7 %. After gonadectomy of roosters at the age of 6 weeks, an increase in body temperature was observed by 1,06º C on the first day and by 1,02º C on the third day of the experiment with constant values of pulse and respiratory movements compared to the control. Оn the 30th day, the gonadectomized roosters showed a change in secondary sexual characteristics, namely, a decrease in the size and color of the crest, the absence of manifestations of aggression, and a significant decrease in vocalization. Оn day 115, the body weight of gonadectomy roosters was higher by 13,2 %, on day 125 - by 10,4 %, on day 135 - by 13,3 % and on day 145 - by 17,0 % compared with the control. On the 20th day, the testosterone content in the blood plasma of gonadectomy roosters decreased by 2.2 times, and on the 185th day – by 2.1 times compared to the control. An increase of 26,9 % in the concentration of uric acid in the blood plasma of gonadectomy roosters was established compared to the control. In the blood plasma of roosters, 21 fractions of proteins with molecular weights from 17 to 260 kDa were found. The largest amount of proteins in the blood plasma of gonadectomy roosters are proteins with molecular masses of 26, 46-50, 190-200 and 230-260 kDa. In the blood plasma of roosters after gonadectomy, compared with the control, the level of proteins with a molecular weight of 110-130 kDa decreased by 1,7 times, 70-76 kDa - by 2,0 times, 46-50 kDa - by 1,4 times and 32 kDa - 1,6 times, and with a molecular weight of 135-160 kDa increased by 1,5 times, 100-106 kDa - by 1,8 times, 63-66 kDa - by 1,4 times and 20 kDa - by 6 times. The average daily weight gain of gonadectomy roosters over the entire period of the experiment was 8.0% higher compared to the control, which contributed to an increase in body weight of the bird by 188 g or 6,4 %. In gonadoectomized roosters after slaughter, the weight of the half-cartridge and cartridge carcasses is higher by 7,5 % and 9,0 %. During gonadectomy in the pectoral muscle of roosters, the fat content increases by 1,8 times compared to the control. The meat of gonadectomy roosters was characterized by high quality and safety indicators. The pH value of water extracts of the studied muscle samples remained within the range of values characteristic of a quality product. Therefore, on the basis of the conducted studies, it can be concluded that gonadectomy of roosters has a positive effect on poultry productivity, changes individual morphological blood parameters and does not affect metabolic parameters and microbial contamination of meat during carcass storage for 4 days at t 4º C. Adler silver roosters should be recommended for the production of poultry meat of good quality using gonadectomy and a longer growing period (up to 185 days).
