The effectiveness of feeding choline in a "protected" form in the post-dairy period of calf rearing

The physiological and productive effect of the developed "protected" form of choline in calves' diets after removing them from milk drinking was studied. Heifers analogs by breed, live weight at the age of three months were divided into 2 groups (n = 10), and received rations by group loose housing system. The animals of the experimental group were daily given minigranules of "protected" choline at the rate of 50 mg/ kg of live weight of the active substance mixed with feed for 90 days, with the study of the aftereffect. For 90 days of feeding the supplement, the additional increase in live weight of animals in the control group was 67.1±0.5 kg, in the experimental group – 77.5±1.2 kg, with an average daily increase in live weight of 745.5±0.01g versus 861.1±0.40 g (p ≤0.05), for 30 days of aftereffect, respectively, 733.3±0.03g versus 836.7±0.09 g. The acceleration of the growth of heifers is interconnected with the improvement of the direction of metabolic processes in their body due to the use of an additive. In the blood serum taken at the end of the experiment, there was noted a higher level of total protein – by 6.3 % (p <0.05); albumins by 8.0 % (p <0.05); creatine – by 7.4 % (p <0.05); glucose (by 21.2 %) (p <0.05); triglycerides by 28.0 % (p < 0.05); cholesterol by 10.2 % (p < 0.05); alkaline phosphatase by 7.6 %, at lower urea levels, by 22.8 % (p < 0.05), and bilirubin by 23.8 % (p < 0.05). According to hematological indicators, higher levels of erythrocyte formation were revealed – by 8.0 % (p<0.05); hemoglobin by 5.2 %; hematocrit index (by 19.5 %), with a lower (by 13.4 %) white blood cell level. A positive effect on the immune status of the organism of growing animals was also found, with a positive difference in the bactericidal activity of blood serum by 4.1 %, a higher level of lysozyme (by 50.0 %) (p≤0.05), phagocytic activity by 1.0 absolute%, phagocytic index by 14.5 %, phagocytic number by 17.5 %. The data obtained prove the relevance of giving choline in “protected” form to growing ruminants.