Determination of flumequine residues in broiler chickens with HPLC and screening method

Abstract

Chickens were used to examine tissue depletion of flumequine after multiple oral doses (12 mg/kg by every 24 h for 5 days). The presence of residues was detected using the microbiological screening method - plate pH 8.0 with E. coli NCIMB 11595 as a test microorganism. The tissue (muscle and liver) concentrations of flumequine were determined using HPLC/Fl method. During the 5 days dosing period, flumequine concentrations in breast muscle and liver exceeded the European Union MRLs (maximal residue limits). After the end of oral administration, hepatic concentrations of flumequine (1760- 90 ng/g) persisted for 3 days; at that time, flumequine residues were also detected in muscle tissue (980-40 ng/g). Flumequine concentrations in breast muscle and liver exceeded the MRL values only on the first day of the withdrawal period. Microbiological method - plate pH 8.0 with E. coli NCIMB 11595 revealed positive results in all samples with residue concentrations above MRL values. Two days of withdrawal period allowed time for the drug concentrations in meat and liver to decrease to an acceptable level prior to slaughter (below MRL).