Abstract
The increase in the rate of intensification of beef cattle breeding, as well as the predicted increase in the number of beef cattle, requires its genetic improvement and necessitates the creation of large-format animals that can maintain high growth for a long time, give heavy carcasses with optimal fat deposition, and have good reproductive qualities and milk production. The article presents the results of testing bulls for their own productivity, also studied the indicators of live weight, constitutional and exterior features of young Aberdeen - Angus breed. Summarizing the results of testing bulls in terms of their own productivity, it should be noted that for a complete reliable assessment of breeding value, the complex breeding index should be taken into account as an indicator that reflects the relative magnitude of the traits and is independent of the conditions of feeding and keeping. With a large number of bulls with the highest indicators of the complex class, the number of bulls with complex indices decreased, which indicates the dependence of the class assessment on the conditions of external factors. Thus, the results of testing bulls for their own productivity were characterized by various qualitative and quantitative indicators of class and index assessments, which makes it necessary to improve the methodology for organizing testing of bulls of meat breeds for their own productivity.