Determination of fluoroquinolones in chicken feces - A new liquid-liquid extraction method combined with LC-MS/MS

The application of antibiotics including fluoroquinolones to farming animals is widespread and may lead to the development of antibiotic resistance and other environmental effects. To calculate environmental loads and for a proper risk assessment it is necessary to determine the antibiotic concentration in feces. Therefore, a new liquid-liquid extraction method combined with HPLC-MS/MS for the detection of marbofloxacin, ciprofloxacin, enrofloxacin and difloxacin in chicken feces was developed. Recoveries ranged from 51.0% to 83.5%. LOQs were between 0.10 and 1.09 mu g/kg. Feces of chickens treated with an enrofloxacin dosage of 10 mg/kg bodyweight revealed maximum enrofloxacin and ciprofloxacin concentrations of 61.3 and 18.8 mg/kg. Both antibiotics could be detected in feces up to two days after the last application in notable amounts (similar to 1 mg/kg). Thus, feces of recently medicated chickens should not be used as a fertilizer without any further processing. (C) 2014 Elsevier B.V. All rights reserved.