The administration of fluoroquinolone antimicrobials to broiler chicken without an adequate withdrawal time may lead to violative concentrations of residues in edible tissues destined for human consumption. To ensure food safety and human health, withdrawal period of enrofloxacin antimicrobial administration, before slaughter need to be studied based on maximum residue limit values in the target tissues. Hence, the present study has been undertaken to evaluate the withdrawal period and depletion of enrofloxacin and its primary metabolite ciprofloxacin residues in broiler chicken in accordance with MRLs set by various regulatory agencies. Group I (6 birds) was kept as untreated control received non medicated water, and Groups II, III, IV, V and VI each 6 birds were administered with enrofloxacin at recommended therapeutic dose 10 mg per Kg body weight, through drinking water for five consecutive days from 43rd to 47th day of age. The plasma and edible tissues viz., liver, kidney, muscle (breast & thigh) and skin were collected and subjected to liquid-liquid extraction followed by enrofloxacin and ciprofloxacin quantification by a validated HPTLC-Fluorescent densitometry assay. Enrofloxacin was well distributed from plasma into tissues and the metabolic conversion of enrofloxacin to ciprofloxacin was observed in all the tissue samples; however the ciprofloxacin concentrations were always lower than that of the parent drug enrofloxacin. Ciprofloxacin was found to be rapidly depleted from the chickens’ body compared to that of enrofloxacin. The withdrawal period for enrofloxacin and its metabolite ciprofloxacin residues in broiler chicken was found to be 5 days and 9 days as per European Union and Japan MRLs respectively.

Highlights

• Depletion of enrofloxacin from chicken’s body was slower than ciprofloxacin.
• The withdrawal period for enrofloxacin in broiler chicken was 5 days and 9 days as per EU and Japan MRLs respectively.