This study investigated gentamicin (GEN) residues in edible tissues of broiler chickens following intramuscular injection and established the withdrawal time (WT) of GEN in poultry edible tissues. Thirty healthy broiler chickens were intramuscularaly injected with GEN at doses of 2.0 mg/kg body weight (BW) once. After drug administration, tissue samples were collected from six broiler chickens at 7, 14, 21, 28, and 42 days post-treatment. GEN residue concentrations in poultry edible tissues were determined using LC-MS/MS. The correlation coefficient values ranged from 0.9976 to 0.9998, and the limits of detection (LOD) and quantification (LOQ) were 0.003-0.008 mg/kg and 0.01-0.025 mg/kg, respectively. Recoveries in muscle, liver, kidney, and fat tissues were 50.39-74.57%, 50.35-66.24%, 65.57-74.23% and 81.62-111.31%, respectively, with coefficients of variation less than 14.17%. In broiler chickens intramuscularally injected with GEN, GEN concentrations in muscle, injection site, liver, and fat samples were below the LOQ on day 14, 21, 42, and 14 post-treatment, respectively. However, GEN was detected in kidney samples at levels above the LOQ up to day 42 after drug treatment. According to the European Medicines Agency’s guideline on the determination of withdrawal periods for edible tissues, the withdrawal period for GEN in liver and kidney samples were established as 38 and 39 days, respectively. In conclusion, the developed analytical method is suitable for detecting GEN in poultry tissues, and the estimated WT of GEN will contribute to ensuring the safety of poultry products.

Abstract
서 론
재료 및 방법
    시약 및 재료
    실험동물
    시험약제 투여 및 시료채취
    표준원액 및 표준용액의 조제
    시료 전처리
    기기분석조건
    분석법 검증
    육계 조직 중 GEN의 잔류휴약기간 설정
결 과
    GEN의 크로마토그램
    검량곡선, LOD 및 LOQ
    회수율과 정밀성
    육계 조직 중 GEN 잔류 분석
    육계 조직 중 GEN 잔류휴약기간 설정
고 찰
감사의 글
REFERENCES

• Kwan Il Park(College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea)
• Yeung Bae Jin(College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea)
• Woo H. Kim(College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea)
• Suk Kim(College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea)
• Hu-Jang Lee(College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea) Corresponding author