The state of protein, lipid metabolism and resistance of Holstein bulls

The state of lipid, protein metabolism and resistance of bulls of producers was studied. A decrease in the activity of lipase, the total amount of lipids, triglycerides was revealed. The cholesterol content was at the level of the minimum physiological value. Creatinine concentration in summer is increased in 60 % of bulls and 17 % in spring, AST - in summer in 30 %, in spring - 13.3% of animals. The carotene content was underestimated in 100 % of the studied animals. The total amount of protein and bilirubin was increased in all animals in all seasons of the year, which indicates excessive protein feeding. The data obtained indicate the need for correction of protein and lipid metabolism in bulls of producers, since disturbances in the metabolism of proteins and lipids negatively affect the resistance indicators.