In the conditions of the analyzed farms, studies were conducted on growing black-motley heifers of different lines. As the results of the conducted studies have shown, the live weight of heifers in all age periods of the studied lines at the analyzed enterprises is at the level of class I standard requirements or exceeds them by 6-11%. The average daily weight gains of heifers of the studied lines at the age from birth to 6 months were 690-820 g, at the age of 6-10 months – 570-810 g, at the age of 10- 12 months – 600-750 g, at the age of 12-18 months – 620-680 g. The relative weight gains of the heifers under study decreased with age; at the age from birth to 6 months the weight gain was 131-142%, from 6 to10 months – 31-48%, from 10 to 12 months – 10.4-16.5%.