Residue depletion of sarafloxacin in black-bone silky fowl tissues after oral administration

In this study, the residue depletion of sarafloxacin in black-bone silky fowl (BSF) was studied after oral doses of sarafloxacin (10 mg/kg BW for 7 consecutive days). Muscle and liver tissues were collected at differentwithdrawal periods and determined by HPLC-MS/MS method. The limit of detection for sarafloxacin was 1.0 mu g/kg, and the recoveries from blank fortified samples were 93.53%similar to 108.47% with coefficients of variation less than 9.28%. At first day after ending sarafloxacin treatment, the mean concentrations of sarafloxacin in muscle and liver were 366.88 +/- 129.51 and 120.35 +/- 46.86 mu g/kg, respectively, higher than their maximum residue limits (10 mu g/kg for muscle, 80 mu g/kg for liver). Notably, the sarafloxacin concentrations in muscle depleted very slowlyand were still up to 45.46 +/- 12.94 mu g/kg at 43.25 days after the last administration. Interestingly, the sarafloxacin concentrations in both tissues increased into peak values at 21 days. In addition, the withdrawal time of sarafloxacinin BSFs should be 93 days as calculated in this study, significantly longer than that (0 day) in common broiler chickens. Therefore, our study provides data for a more prudent use of sarafloxacin in BSFs and suggests a withdrawal time of 93 days was necessary to guarantee safety in BSFs for the consumers.