DYNAMICS OF ORIGIN AND METHODS OF EVALUATING BREEDING VALUE OF BULLS IN UKRAINIAN CATALOGUES

The article analyzes the dynamics of using dairy and dual-purpose bulls with a determined breeding value in Ukrainian catalogues over the period 2011–2025. The research material included official annual bull catalogues for the reproduction of the dam stock, based on which the structure of the listed sires was assessed according to their country of origin and breeding value determination methods. The study applied methods of statistical analysis, comparison, generalization, and a systemic approach. A significant reduction in the share of domestically sourced bulls and an increased role of imported genetics have been established. The proportion of domestic bulls critically decreased from 52.0% (2011) to 15–16% (2024–2025). In contrast, semen production from the USA took a leading position, with its share increasing to approximately 50%. A significant transformation in bull breeding value evaluation methods was revealed: genomic prediction became dominant (nearly 50% in 2024–2025), ensuring high repeatability (> 80%) and the highest selection index values. The BLUP method maintains stability and high reliability (90–94% repeatability), while traditional domestic evaluation methods gradually lost relevance and were replaced by modern calculation-based and international approaches. Changes in the catalogue structure and evaluation methods indicate the need to combine the advantages of global genetics with the development of proprietary national evaluation systems to ensure food security and sustainable genetic progress in Ukraine's dairy cattle breeding sector.