PRODUCTIVITY AND METABOLISM OF SUBSTANCES IN THE BODY OF BULLS BY OPTIMIZING THEIR PROTEIN NUTRITION

The issue of optimizing the protein nutrition of bulls by keeping them in the territory belonging to the III zone of radioactive contamination due to the Chernobyl accident is considered. Experimental studies on young cattle of the Ukrainian black-and-white dairy breed were conducted in the conditions of the physiological yard of the Institute of Agriculture of the Polissya NAAS. For the experiment, 2 groups of experimental animals were formed: Group I (control) – protein deficiency in the diet was provided by feeding 1.02 kg of pea shoots (Pisum sativum L.), and in Group II (experimental) – the same amount of field peas (Pisum sativum, var arvence). Since different types and amounts of feed were used for feeding the bulls, optimization of the nutritional value of the feed rations was carried out monthly. The experimental animals were kept in the same room according to the adopted technology – in stalls on a leash. The feeding and watering regime, microclimate parameters in both groups were the same. Optimization of protein nutrition of fattening bulls due to various high-protein feeds has a positive effect on productivity (875-1023 g) and feed conversion (103.0-120.4 MJ), does not have a negative effect on the slaughter qualities of animals. At the same time, the use of field peas compared to peas to ensure the normalized need of young cattle in digestible protein contributed to an increase in the average daily gain of live weight of animals by 16.9% (P>0.95) while reducing the expenditure of metabolic energy per unit of gain by 14.5%. The introduction of field peas into the diet of fattening bulls compared to the use of peas contributed to better digestion of dry matter by 0.2% abs., crude protein – 3.9 (P>0.95) and fiber – by 0.9% abs. Experimental animals of group II digested crude fat (by 1.4% abs.) and BER (by 0.3% abs.) somewhat worse than their peers of group I. At the same time, the Nitrogen balance in the body was better in the experimental group bulls compared to the control by 2.9%.