Biochemical characteristics of calves of the Holstein breed of different age groups in winter

Abstract

Relevance. The periods of early postnatal ontogenesis are characterized by high plasticity, intensive metabolism and the need for nutrients and biologically active substances. Young animals weakened by diseases lag behind in growth and development, labor and feed costs for its cultivation increase. Maintaining and preventing the health of calves during growth and development is an important problem in modern animal husbandry.Methods. The work was carried out at the Federal Research Center for Animal Husbandry named after Academy Member L.K. Ernst in 2021–2022 and on the basis of «Agrofirma “Zarya”» LLC, Bogorodsky district, Nizhny Novgorod region. The experiments were carried out on heifers of different age groups (2 months — group I; 6 months — group II; 12 months — group III). In total, 36 female (calves), 12 heads in each group, were used in the experiment.Results. A significant difference was found between groups I and II in: total protein level, «albumin — globulin» ratio (A/G), cholesterol, iron, AST at the level of p < 0.05; globulin p < 0.01; bilirubin and creatinine p < 0.001. Between groups I and III, the reliability was established by phosphorus p < 0.05; between groups II and III — a highly reliable difference at the level of p < 0.001 in phosphorus, ALT and alkaline phosphatase, as well as the ratio «calcium — phosphorus» (Ca/P).