NATURAL BIOLOGICALLY ACTIVE PREPARATION FOR FEEDING CALVES

The objective of the study is to evaluate the efficacy of a biologically active sapropel preparation in feeding farm animals and to assess its impact on the productivity of young animals. The study was conducted on Holstein calves aged four months and older, after weaning, at the Yermolinskoye peasant farm in the Novgorod Region. The study assessed the preparation's impact on the digestibility of dietary nutrients, the biochemical status of the experimental animals, absolute and average daily weight gain, and feed conversion. Three groups (n = 10) were formed using the analog-matching principle: a control group and two experimental groups. In addition to their main diet, calves in the experimental groups consumed 5 and 10 ml of the supplement, respectively. The use of 5 ml of this supplement increased the digestibility of the main feed nutrients by 1.56–3.73 percentage points and increased the protein index, which indicates an increase in the intensity of protein metabolism, bringing it closer to the normal value of 0.76 g/l. The absolute and average daily gain of calves in the first experimental group exceeded the corresponding figure for animals in the control group by 8.8 % (P < 0.001). The use of 5 ml of UDGSS reduced the cost of digestible protein per 1 kg of live weight gain by 8.2 %, energy feed units by 8.1 %, and metabolizable energy by 9 % compared to the control. Increasing the mass dose of the supplement led to an increase in the cost of digestible protein and metabolizable energy per unit of weight gain by 14.8 and 14.9 % respectively. Experimental data showed that the optimal dose of the UDGSS dietary supplement in the diets of young animals aged four to twelve months is 5 ml per head per day. Increasing the dosage to 10 ml is unjustified, as it not only fails to enhance the positive effect but, on the contrary, worsens physiological and production indicators.