Abstract Holsteinized black-and-white cattle are used for milk production. The genealogical structure of the herd is represented by animals from the following genealogical lines: Vis Back Ideal 1013485, Reflection Sovering 198998, Montwick Cheiftain 95679, Pabst Governor 882933 and Annas Adema 30587. Animals of these types feature high milk productivity indices. In particular, the cows of all the researched lines have high milk productivity indices - more than 9,000 kg of milk per lactation. The highest milk yields are achieved by cows of the Montwick Cheiftain 95679 line. The yields are 16-339 kg higher than ones of the animals from the Annas Adema 30587 and Pabst Governor 882933 lines, respectively. According to the quality indices of milk, cows of all lines exceed the requirements of the breed standard. Data on amount of milk fat confirms the level of breeding value of the cattle breeding stock used in the farm. They exceed the breed standard in terms of milk fat yield by more than 2 times. The highest coefficient of the cows’ biological efficiency was recorded in the cows groups of Annas Adema 30587 and Montwick Cheiftain 95679 lines, and the biological full-value was confirmed for the Montwick Cheiftain 95679 and Pabst Governor 882933 lines.