Plasma and tissue depletion of florfenicol and florfenicol-amine in chickens.
Chickens were used to investigate plasma disposition of florfenicol after single intravenous (i.v.) and oral dose (20 mg kg-1 body weight) and to study residue depletion of florfenicol and its major metabolite florfenicol-amine after multiple oral doses (40 mg kg-1 body weight, daily for 3 days). Plasma and tissue samples were analyzed using a high-performance liquid chromatography (HPLC) method. After i.v. and oral administration, plasma concentration-time curves were best described by a two-compartment open model. The mean [ +/- standard deviation (SD)] elimination half-life (t1/2beta) of florfenicol in plasma was 7.90 +/- 0.48 and 8.34 +/- 0.64 h after i.v. and oral administration, respectively. The maximum plasma concentration was 10.23 +/- 1.67 microg mL-1, and the interval from oral administration until maximal concentration was 0.63 +/- 0.07 h. Oral bioavailability was found to be 87 +/- 16%. Florfenicol was converted to florfenicol-amine. After multiple oral dose (40 mg kg-1 body weight, daily for 3 days), in kidney and liver, concentrations of florfenicol (119.34 +/- 31.81 and 817.34 +/- 91.65 microg kg-1, respectively) and florfenicol-amine (60.67 +/- 13.05 and 48.50 +/- 13.07 microg kg-1, respectively) persisted for 7 days. The prolonged presence of residues of florfenicol and florfenicol-amine in edible tissues can play an important role in human food safety, because the compounds could give rise to a possible health risk. A withdrawal time of 6 days was necessary to ensure that the residues of florfenicol were less than the maximal residue limits or tolerance established by the European Union.
Anadón
Arturo
A
Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, Madrid, Spain.
Martínez
Maria Aranzazu
MA
Martínez
Marta
M
Ríos
Alba
A
Caballero
Virginia
V
Ares
Irma
I
Martínez-Larrañaga
Maria Rosa
MR
D000818:Animals; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D002645:Chickens / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005506:Food Contamination / Q000032:analysis; D006207:Half-Life; D008460:Meat / Q000032:analysis; D013839:Thiamphenicol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics
D000900:Anti-Bacterial Agents; C083312:florfenicol amine; C035534:florfenicol; D013839:Thiamphenicol