Effect of experimental replacer of dry skimmed milk on physiological state and performance of calves of 65-115 days of age
Authors:   Volga Region Research Institute of Manufacture and Processing  of Meat-and-Milk Production, Gorlov I.F. , Slozhenkina M.I. ,   Volga Region Research Institute of Manufacture and Processing of Meat-and-Milk Production, Radchikov V.F. ,   Scientific Practical Centre of Belarus National Academy of Sciences on Animal Breeding, Radiko M.E. ,   Scientific Practical Centre of Belarus National Academy of Sciences on Animal Breeding, Prilovskaya E.I. ,   Scientific Practical Centre of Belarus National Academy of Sciences on Animal Breeding
Published: June 2021

Aim. To study the effect of experimental replacer of dry skimmed milk on physiological state and per-formance of calves of 65-115 days of age. Materials and Methods. Zootechnical, biochemical and mathematical methods of analysis were used in the course of research. The obtained digital material was processed using method of varia-tion statistics, considering the Student-t validation criteria, using the Microsoft Excel software package. Results. Studies helped to determine that feed intake in calves during the experiment on studying the efficiency of dry skimmed milk replacer used for feeding calves at the age of 65-115 days was nearly the same. Study of biochemical composition of blood of experimental animals indicates that inclu-sion of dry skimmed milk replacer and whole milk replacer in the diet instead of whole milk had no negative effect on physiological state of animals. During the experiment, blood indices were record-ed to be within physiological standards, which indicates the normal course of metabolic processes in calves of experimental groups. According to the results of blood analysis in young animals of the II and III experimental groups, an increase in concentration of total protein by 13.5 and 15.4%, glu-cose – by 6.5 and 7.3%, calcium – by 14.4 and 14.9%, phosphorus – by 16.5 and 17.3% had been determined in comparison with control analogues. The urea level in blood of young animals of the experimental groups was 3.5 and 4.5% lower compared to control. Study of growth dynamics showed that dry skimmed milk replacer and whole milk replacer used instead of whole milk in the di-et for calves aged 65-115 days had an insignificant effect on the average daily body weight. So, young animals consuming whole milk reached the average daily weight gain of 982 g, and their co-evals from II and III experimental groups 964 and 970 g, respectively. Feed costs per 1 kg of weight gain were recorded to be nearly at the same level. Cost of daily diet in experimental groups turned to be 10.3 and 5.8% cheaper compared to the control. Calculation of economic efficiency of use of dry skimmed milk replacer and whole milk replacer by animals in diet showed a decrease in price cost of weight gain by 8.5 and 4.8%. Conclusion. Based on the research conducted it has been determined that feeding 10-65 days of age calves with experimental milk replacer allowed to obtain 970 g of the average daily weight gain for the experiment period, or 1.2% lower than the control indicator. Feeding calves whole with milk re-placer helps reduce the cost of diet by 5.8% and price cost of weight gain by 4.8%, when feeding with skimmed milk replacer these indicators made 10.3 и 8.5 percent.