Abstract
The article presents the results of establishing a Kazakhstan reference population of the Holstein breed and assessing the breeding value of animals based on genomic analysis. A reliable database was developed for first-lactation cows based on 305-day lactation records, including the collection and genotyping of 2,980 biological samples using a panel of more than 50,000 SNP markers. Biological material was obtained from animals in nine breeding farms involving 89 service sires, ensuring sample representativeness and broad genetic coverage. Based on calculated genomic estimated breeding values (GEBV), a comprehensive Genomic Holstein Global Index (GHGI) was developed, incorporating milk production traits, conformation, health, longevity, and manageability. The distribution of GHGI and GEBV for milk yield approximated normality with slight positive skewness, indicating targeted selection of animals with high genetic potential. Carriers of hereditary anomalies HH1, HH3, HH4, HH5, and CVM were identified at low frequencies, emphasizing the necessity of genetic monitoring in breeding programs. The results confirm the effectiveness of integrated genomic selection for accelerating genetic progress, improving productivity, and ensuring genetic safety of the Holstein population under Kazakhstan conditions.