Abstract: Precision breeding and efficient reproduction in dairy core herds constitute a core technological system for improving quality and efficiency,addressing germplasm resource constraints,and upgrading improved varieties in large-scale dairy farming. In view of industry challenges such as insufficient coverage of improved varieties,slow genetic progress,uneven reproductive efficiency,and short productive lifespans of high-yielding dairy cows in domestic farming,this paper systematically reviewed the entire technical framework,from core herd establishment,breeding objective setting,and selection/introduction of replacement heifers,to precision feeding and breeding,and dynamic culling and renewal,grounded in animal breeding and quantitative genetics theories and integrated with practical farm operations. The paper integrated modern reproductive technologies including genomic selection,MOET （multiple ovulation and embryo transfer）,and sex-sorted frozen semen, clarified key practical points in precise nutrition,disease prevention and control,and digital data support,analyzed implementation challenges and medium-to-long-term benefits,and proposed optimization plans suitable for various types of farms. By building dynamic iterative core breeding populations in line with actual farm production,and combining precision nutrition,advanced reproductive technologies,and digital management,the genetic structure of the herd can be continuously optimized,thereby improving milk yield,milk quality,reproductive performance,and longevity. After 3–5 years of targeted selection,the overall genetic level of the whole farm can be significantly elevated. This paper provided practical guidance for improved breeding in large-scale farms and offers theoretical support for the self-sustainable development of China's dairy cattle breeding industry.

Key words: core herd, precision breeding, reproductive strategy, genetic improvement, genomic selection, large-scale farming