恩诺沙星在养殖大菱鲆体内的残留及消除规律

The residue of Enrofloxacin and its elimination in cultivated Scophthalmus maximus

关键词:  恩诺沙星  大菱鲆  消除

Key words:  Enrofloxacin  Scophthalmus maximus  Elimination

摘要:

在11～12 ℃水温条件下，对大菱鲆Scophthalmus maximus连续口服恩诺沙星7 d后肌肉、血清和肝脏组织中该药物及其代谢产物环丙沙星的残留及消除规律进行了研究。大菱鲆肌肉、血清和肝脏中残留的恩诺沙星药物用二氯甲烷提取，在不同的时间点利用反相高效液相色谱荧光检测法检测药物浓度，最低检测限为0.01 μg/ml，平均回收率为75%～87%。研究结果表明，恩诺沙星按一级动力学过程从体内消除，在3种组织中消除速率不同，在肌肉、血清和肝脏中的消除曲线方程分别为C=1.560e-0.0310 t、C=1.147e-0.018 9 t和C=0.920e-0.027 1 t；恩诺沙星在3种组织中的消除半衰期较长，分别为22.53、36.67和25.57 d。在给药后的第94天，肌肉组织中的恩诺沙星浓度持续保持0.168 μg/g，尽管NY5070 2002无公害水产食品中恩诺沙星和环丙沙星的残留限量MRL（Maximum residue limit）要求为0.05 μg/g，但本试验数据提示，大菱鲆肌肉组织中残留的恩诺沙星和环丙沙星超过了标准，建议合理的休药期应不少于120 d。

Abstract:

Turbots Scophthalmus maximus (BW 300~400 g) were kept in experimental tanks with aerated seawater at temperatures of 11～12 ℃. The fish were fed enrofloxacin (EF) medicated feed at a EF dosage of 30 mg/kg BW. per day for 7 consecutive days. Serum, muscle and liver tissues were taken from five turbots at days 1, 2, 4, 8, 12, 16, 22, 28, 36, 44, 54, 64, 74, 84, 94 after the last oral administration of EF. The three tissues were tested by high performance liquid chromatography (HPLC) with fluorescence detection, the minimum detection limit was 001 μg/ml, average recovery was 75～87% . The results showed that elimination of EF complied with the first order kinetics, and the equations of elimination curve of enrofloxacin in muscle, liver, serum were C=1.560e-0.031 0 t, C=1.147e-0.018 9 t and C=0.920e-0.027 1 t, respectively.The elimination half lives (T1/2elim β) were 22.53, 36.67, 25.57 d, respectively. It is suggested that a withdrawal time of more than 120 d at temperatures of 11～12 ℃ is appropriate for the elimination of enrofloxacin and ciprofloxacin in turbot.