Analysis of pedigree structure and inbreeding coefficient for Jersey dairy cattle in Korea

This study was conducted to analyze the pedigree information of the Korean Jersey dairy cattle breed and to determine how the inbreeding coefficient is changing. A total of 3,624 pedigree data for 976 Jersey cows were used for the analysis, and the pedigree completeness index (PCI) and inbreeding coefficient by birth year were calculated and compared. As a result of the PCI analysis, PCI1, PCI3, and PCI5 were all over 90%, confirming that the pedigree information was well managed. However, the inbreeding coefficient analysis results confirmed that the inbreeding coefficient exceeded 5% after 2020 and increased by 0.2% every year. In particular, after 2020, the proportion of individuals born through embryo transfer and artificial insemination using domestically produced embryos increased. The decrease in the number of individuals used as sire compared to the number of mating heads at that time was found to be one of the reasons for the increase in the inbreeding coefficient of the Jersey breed. In order to develop the sustainable Jersey breed industry, it is necessary to continuously manage pedigree and implement design mating program.