Accumulation and clearance of orally administered erythromycin in adult Nile tilapia (Oreochromis niloticus)

Nile tilapia (Oreochromis niloticus) were medicated with erythromycin base via the medicated ration at 50 mg and 100 mg erythromycin·kg^-¹ fish body weight^-¹·d^-¹ for 7 days. Erythromycin residues in their muscle were determined by LC-MS/MS method through TUV Rheinland Aimex Vietnam Co., Ltd. The results predicted withdrawal time for Nile tilapia was 33 days (908°C-day) if treated by the former dose or 42 days (1150°C-day) if treated by the later one under our experimental conditions. Derivative biotransformation of erythromycin such as erythromycin C, E, F appeared in post-dosing stage, all of them were depleted to safe level if we strictly followed the withdrawal time and chemotherapeutic dosage as recommendation.