Productivity and blood parameters of calves of different age groups when using a feed mixture based on humic acids

The effectiveness of the use of an organic feed mixture based on humic acids on body weight gain, average daily gains and blood parameters of calves of different age groups was analyzed. For 50 days, dairy calves aged 0 to 50 days and heifers of the experimental group aged 3–4 months were fed a feed mixture based on humic acids in the amount of 20 g/100 kg of animal body weight. The drug was added to milk (colostrum) of dairy calves and to water of heifers aged 3–4 months. The effectiveness of the use of humic acids was monitored by monitoring the body weight of animals at the beginning of the study and at the end of the study (after 50 days). Morphological, physical and biochemical blood parameters of animals were determined at the beginning of the study and at its end. Body weight of dairy calves and heifers 3–4 months age of the experimental group at the end of the experiment significantly increased (p˂0.05) and (p˂0.001), respectively, compared with the control group. Average daily gains exceeded the values of dairy calves (p˂0.001) and heifers 3-4 months of age (p˂0.05) of the control group, which indicates the ability to improve the digestibility of the diet, stimulating microbial activity in the intestine and, thus, improving the absorption of nutrients. According to the results of biochemical studies, changes in hemoglobin concentration in the blood of the experimental groups of dairy calves and heifers 3-4 months of age (p˂0.1), but they were not statistically significant. Along with this, at the end of the experiment, the heifers of the experimental group showed a slight increase in erythrocytes from 5.52±0.64 to 7.1 ± 0.60 T/l (p˂0.1) and a slight increase in the respiratory surface of erythrocytes due to an increase in the average volume of erythrocytes (p˂0.1), but these changes were not significant. The study of biochemical parameters of the blood serum of dairy calves of the experimental group indicates an increase in the concentration of total protein at the end of the experiment and total calcium at p˂0.1, but the changes were not statistically significant. In the blood serum of heifers of the experimental group of 3–4 months of age, the amount of total protein increased (p˂0.05), which indicates an improvement in the assimilation of proteins from the consumed feed. Humic acids have a positive effect on the mineral metabolism of 3–4-month-old heifers. age, in particular on the concentration of total calcium in blood serum (p˂0.05), which indicates an improvement in its absorption. Key words: humic acids, total protein, total calcium, inorganic phosphorus, blood serum, dairy calves, heifers.