Experimental studies have shown an increase in productivity, metabolic processes, the effectiveness of the use of nutrients and biologically active substances and the metabolic energy of diets, the health of heifers aged 1–6 months under the conditions of industrial technology of their rearing. Increasing the productivity of heifers is closely related to improving the nutrition system during all periods of rearing with the use of the vitamin complex Vitaminol in diets depending on their age and body weight. The highest effectiveness of rearing young animals has been established when using Vitaminol in doses: 1,3 g/head./day – up to 1 month, 2,4 g/head./day – 2 months, 3,3 g/head./day – 3 months, 4,3 g/head./day – 4 months, 4,8 g/head./day – 5 months and 5,3 g/head./day – at the age of 6 months. Differentiated feeding of optimal doses of feed additives to calves increases the digestibility of dry matter by 1,41–10,8 %, organic matter by 1,6–10,0 %, raw protein by 1,6–6,8 %, raw fat by 1,4–8,7 %, raw fiber by 1,5–3,0 % and nitrogen-free extractive substances by 1,6–6,0 % depending on age and body weight (from 1 to 6 months inclusive). It has a positive effect on the absorption of nitrogen and the use of calcium and phosphorus in the body. The use of Vitaminol in diets of calves contributes to an increase in live weight and average daily gain compared to the control group. In calves up to one month of age (at the dose of 1,3 g/head/day) live weight increased by 6,5 %, the average daily gain by 11,4 %, in 2 months (at the dose of 2,4 g/head/day) these indicators were 2,9 and 2,6 %, respectively, at 3 months (at the dose of 3,3 g/head/day) – 3,4 and 8,2 %, in 4 months (at the dose of 4,3 g/head/day) – 6,7 and 12,8 %, in 5 months (at the dose of 4,8 g/head/day) – 4,4 and 3,6 % and at 6 months (at the dose of 5,3 g/head/day) – 4,3 and 2,7 %, respectively. In order to improve the quality of feeding when rearing calves, more fully realize their genetic potential, increase productivity and use of nutrients in diets and normalize metabolic processes in the body we recommend the optimal doses of the feed additive Vitaminol depending on age (g/head/day): 1,3 – in 1 month, 2,4 – in 2 months, 3,3 – in 3 months, 4,3 – in 4 months, 4,8 – in 5 months, 5,3 – in 6 months. Feed additive Vitaminol enter into the composition of complete feed, wet feed mixtures and feed to calves 1 time per day.