Efficiency of using mixed feeds with different levels of lysine and methionine for growing turkeys

The purpose of the study was to investigate the effect of feeding complete mixed feeds with different levels of lysine and methionine on the growth of young turkeys. Experimental studies were performed on young meat turkeys of the BIG 6 cross. Based on the method of balanced groups, five experimental groups of day-old poultry were established. The experiment lasted 126 days and was divided into two periods: equalising (7 days) and main (119 days). During the equalising period, the experimental young animals consumed mixed feed of the control group. During the main period of the experiment, the amount of lysine and methionine relative to the mixed feed of poultry of the control group for the rearing periods decreased or increased proportionally by 5% and 10%. It was found that different levels of lysine and methionine in mixed feeds for young turkeys affect their productivity in different ways. At the age of 126 days, turkeys that received mixed feed with an increase in the amount of lysine and methionine by 5% and 10% had the highest live weight – they outnumbered the analogues of the control group by 5.9% (p < 0.01) and 3.6%, respectively. Young animals that consumed mixed feed with a reduced amount of lysine and methionine in this indicator were inferior to their control peers by 5.6% (p < 0.05) and 2.7%, respectively. An increase in the level of lysine and methionine by 5% and 10% in mixed feed of turkeys at all stages of their growth helps to reduce feed costs per 1 kg of live weight gain by 4.3% and 2.1%, respectively. It is proved that the relationship between the levels of lysine and methionine in mixed feed for young turkeys and its costs per 1 kg of live weight gain is described by a polynomial line with a reliable approximation coefficient R2 = 1. Correlation analysis shows that there is a significant (p < 0.05) strong inverse relationship between these two indicators (rs = -0.82). The poultry liveability index in all experimental groups was close (94-96%), but the probable influence of different levels of lysine and methionine in mixed feed during poultry rearing on its liveability indicator was not established