Oxytetracycline residues in rainbow trout analysed by a rapid HPLC method

Abstract

A rapid and sensitive HPLC method was developed for the determination of oxytetracycline in fish tissues (muscle and liver) based on a clean-up and concentration procedure on Sep-Pak C18. At a coastal fishfarm rainbow trout (Salmo gairdneri) suffering from Vibrio anguillarum were treated with 75 mg oxytetracycline per kg fish and day for ten days. Oxytetracycline residues above the limit of determination (0.005 micrograms/g) were found in fish 82 days after treatment. The recoveries from spiked tissues were about 60% and 70% for muscle and liver, respectively.