Analysis of Protein Metabolism by Biochemical Parameters in Holstein Cows for Preventing the Reproductive System Pathologies

Introduction . Protein metabolism disorder (dysproteinemia) in dry and freshly calved cows often becomes a complicating factor during mastitis and endometritis and leads to the animal's liveweight decrease. Timely detection of physiological disorders and diseases in the highly productive animals by means of a biochemical blood test is the basic method to preserve the optimal indicators of herd productivity and prevent the economic losses, however, this issue is insufficiently followed up in the dairy farms. The aim of the present research is to analyse the protein metabolism in highly productive Holstein cows by biochemical parameters for timely prevention of the dysproteinemia and pathologies of the reproductive system. Materials and Methods. The research was carried out in the conditions of a large dairy farm in the Central district of the Russian Federation in the period from March to June 2019. The objects of the research were 45 highly productive Holstein cows (dry, freshly calved and milking cows — 15 heads in each group). To analyse the protein metabolism and inflammatory processes in the tissues and organs of dry and freshly calved cows, the following biochemical blood parameters were studied: total protein, albumin, globulin, urea, creatinine, uric acid, transferase enzymes — ASAT and ALAT. The analysis was carried out by comparing the results obtained with the normal values of physiological parameters. Results . In 5 out of 15 dry cows, the albumin level was 5.3–16% lower, and in freshly calved cows it corresponded to the lower limit of the physiological norm values. The total protein in the blood of the freshly calved cows was lower than normal by 20–23%, on average. The concentration of urea in blood of all cows under research was reduced by 1.5– 2.5 times, creatinine was 2–2.5 times elevated (56–89%). The ASAT enzyme activity in 75% of dry and in all freshly calved cows was 2–4 times higher. The reserve alkalinity parameter was 0,6–2,4 times less than the physiological norm values in all animals under research. Discussion and Conclusion . During the research it was found that the compliance of the protein level in the diet of productive animals with the biological needs of their organisms should be determined by the concentration of total protein and albumin in the blood serum, and dysproteinemia and various pathologies of the reproductive system — by the content of urea, creatinine and activity of the aspartate aminotransferase (ASAT) enzyme.