Content and variability of nitrogen metabolism in cattle of the Holstein breed under conditions of Western Siberia

Abstract

It is necessary to assess the state of nitrogen metabolism to deepen control over the usefulness of feeding cattle and ensure prompt response to nutritional imbalances and diet adjustments. Nitrogen balance is a key indicator of cattle metabolism. The authors presented the results of determining the content and variability of indicators of nitrogen metabolism in Holstein cattle in Western Siberia. The object of the study was the bulls of the Holstein breed, obtained from four sires in the conditions of industrial livestock enterprises in the West Siberian region. The authors also studied the main indicators of protein and non-protein nitrogen metabolism (using Vector-Best reagent kits): total protein, albumin, globulin, urea, creatinine, and uric acid. It was found that the indicators of total protein, albumin, globulins, urea, and uric acid were within the generally accepted boundaries of the physiological norm for cattle. However, the albumin-globulin coefficient was below the norm, and the creatinine level was above the physiological norm. The content of urea and creatinine and the albuminglobulin coefficient were characterized by the highest rates of variability, which indicates the heterogeneity of this population sample of Holstein cattle in terms of the peculiarities of the course of protein metabolism. The authors did not reveal statistically significant intergroup differences in the content of total protein (p = 0.67), albumin (p = 0.23), globulins (p = 0.87), albumin-globulin coefficient (p = 0.96) and urinary acids (p = 0.31) using the Kruskal-Wallis test. However, the authors established the influence of the father on the level of urea (p = 0.049) and creatinine (p = 0.042) in the blood serum of the offspring. The analysis of the protein gram and the level of uric acid in the blood serum of the offspring did not reveal significant differences in the influence of the father while differences were established in the level of end products of protein metabolism - urea and creatinine.