Drug Withdrawal from Farmed Fish: Depletion of Oxytetracycyline Sulfadiazine and Trimethophrim from Muscular Tissue of Rainbow Trout (Salmo Gairdneri)

摘要

A statistical approach to the setting of withdrawal times is presented. It is suggested that the time intercept between detection limit of the applied method of analysis, and the 90 % upper prediction limit of a linear regression on the logarithm of the tissue drug concentration provides a realistic estimate of the necessary withdrawal period at the temperatures considered. Recognizing that water temperature is an important determinant of pharcnaco-kinetics in fish, temperature-dependent withholding periods are recommended, i.e. 60 days at temperatures above 10°G and, for oxytetracycline, 100 days at temperatures between 7 and 10°G. The observed persistence of sulfadiazine and trimethoprim at lower water temperatures indicates that this drug mixture should be applied to slaughter fish only during summer.