Establishment of defined daily doses for veterinary antimicrobials in food-producing animals in the Republic of Korea and comparison with European Medicines Agency values

Introduction. Antimicrobials are essential for maintaining animal health; however, their use exerts selective pressure that promotes antimicrobial resistance. Therefore, monitoring antimicrobial use (AMU) is critical for managing the emergence and selection of resistance and various metrics have been developed in veterinary medicine to monitor these usage patterns. Gap statement. Although metrics such as sales volume are widely used, they do not account for differences in antimicrobial potency. Currently, no defined daily dose metric specific to food-producing animals in Korea has been established to accurately assess domestic usage patterns. Aim. In this study, we aimed to establish defined daily doses for Republic of Korea (DDDkr) for antimicrobial agents approved for use in cattle, pigs and poultry and to compare these values with the defined daily doses for animals (DDDvet) established by the European Medicines Agency (EMA). Methodology. A total of 931 veterinary antimicrobial products approved and marketed with recorded sales volumes for food-producing animals in the Republic of Korea as of 2023 were analysed. DDDkr were defined following EMA principles, based on species, administration route and antimicrobial agents. To quantitatively compare the derived DDDkr values with existing DDDvet standards, the quotient of daily defined doses (QDDD) was calculated. Results. We established 200 DDDkr values: 80 for cattle, 80 for pigs and 40 for poultry. Existing DDDvet values covered 57.5% of Korean veterinary antimicrobials, as certain formulations (sprays, intramammary and intrauterine products) lacked comparable EMA values. Median QDDD values were 0.87 for cattle, 0.79 for pigs and 0.75 for poultry, reflecting significant differences between DDDkr and DDDvet for cattle and pigs ( P <0.05), whereas no significant difference was observed in poultry. Comparative analysis showed that most QDDD values were less than 1. Conclusion. This study is the first to establish a DDDkr for food-producing animals in Korea. The results indicate that national dosages are generally lower than those defined in European standards, highlighting the need for country-specific metrics such as DDDkr to ensure more accurate domestic AMU monitoring.