Biochemical processes in cows and the biological value of milk under influence of cobalt citrate

Abstract

The aim of research was to study the effect of different amounts of cobalt citrate produced by nanotechnology on biochemical processes in cows, their productivity and biological value of milk in the first two months of lactation. To achieve this goal the subsequent problems have been solved. We investigated the effect of different amounts of cobalt citrate on biochemical parameters of blood and milk of cows and controlled their average daily yield. The experiment has been conducted in 3 groups of cows (5 cows each) of Ukrainian black and white dairy cattle, analogue by body weight (590–620 kg), performance (6,5–6,8 thousand kg of milk per past lactation) and lactation (3–4 lactation). Unlike the control cows, animals experimental (ІІ) group for two months were fed by mineral supplements in the form of cobalt citrate in an amount of 19 mg Co/kg of dry matter of diet and research (ІІІ) – cobalt citrate in an amount of 34 mg Co/kg of dry matter of diet. Duration of cobalt citrate feeding of cows of research groups was 2 months. In all groups of cows the samples of venous blood were taken in preparation for feeding additives period and during 60 day of additives feeding period in order to determine the concentration of total protein, ceruloplasmin, sialic acids, hexoses bound to proteins and activity of amino transferases. The milk production has been controlled in days of sampling with the definition of daily milk yield per cow and taking an average sample for the determination of milk fat, protein, lactose, inorganic phosphorus and calcium. It has been established that the inclusion in the diet of cows of experimental (ІІ) group of mineral supplements contributed to an increase in animal blood total protein content by 11.9% (P < 0.05), inorganic phosphorus by 15.3% (P < 0.05) and hexoses bound protein by 8.8% (P < 0.05). Under these conditions milk content of inorganic phosphorus increased by 5.6% (P < 0.05) and average daily milk production increased by 4.5%. The use of mineral additives in third experimental group of animals within two months contributed to an increase in blood ceruloplasmin content by 5.1% (P < 0.05) and hexoses bound protein by 11.5% (P < 0.01). Mineral supplements promote 5.4% raise of average daily milk production and increase it to the lactose content by 0.10% (in absolute).