OXYTETRACYCLINE, SULFADIMETHOXINE, AND ORMETOPRIM RESIDUES IN CHANNEL CATFISH BY HPLC

摘要

HPLC methods and modified extraction procedures were used to analyze residues of oxytetracycline (Terramycin, OTC) or sulfadimethoxine (SDM) and ormetoprim (OMP) in channel catfish fed OTC or Romet-30 under controlled conditions. Mean recovery rates in fish muscle were 92.5% for OTC over concentrations of 0.05-1.0 ppm and 86.3% for OMP and 87.9% for SDM over 0.05-5.0 ppm. SDM and OMP were rapidly depleted from large catfish (about 345g) after 5 days feeding with Romet-30 at 50-100 mg/kg body weight. By day 2 post-treatment, no residue was detected. Residues of OTC, SDM and OMP were also detected in fingerling channel catfish (about 20.3g) after 4 and 8 wk of feeding with Romet-30 or OTC at 12.5, 25, or 50 mg/kg body weight, but not after a S-wk-withdrawal period.