title: Plasma disposition and tissue depletion of chlortetracycline in the food producing animals, chickens for fattening.
abstract: Chickens were used to investigate plasma disposition of chlortetracycline after single IV (15 mg/kg) and multiple oral administration (60 mg/kg, 5 days) and residue depletion of chlortetracycline after multiple oral doses (60 mg/kg, 5 days). Plasma and tissue samples were analyzed by HPLC. Mean elimination half-lives in plasma were 7.96 and 13.15 h after IV and multiple oral administration. Maximum plasma concentration was 4.33 μg/ml and the interval from oral administration until maximal concentration was 1.79 h. Oral bioavailability was 17.76%. After multiple oral dose, mean kidney, liver and muscle tissue concentrations of chlortetracycline+4-epi-chlortetracycline of 835.3, 192.7, and 126.3 μg/kg, respectively, were measured 1 day after administration of the final dose of chlortetracycline. Chlortetracycline residues were detected in kidney and liver (205.4 and 81.7 μg/kg, respectively), but not in muscle, 3 days after the end of chlortetracycline treatment. The mean chlortetracycline+4-epi-chlortetracycline concentrations were below LOQ at 3 and 5 days after cessation of medication in muscle and liver, respectively. A withdrawal time of 3 days was necessary to ensure that the chlortetracycline residues were less than the maximal residue limits (MRLs) established by the European Union (100, 300, and 600 μg/kg in muscle, liver, and kidney, respectively).
authors.affiliation: Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain. anadon@vet.ucm.es
authors.forename: Arturo
authors.initials: A
authors.lastname: Anadón
authors.forename: Felipe
authors.initials: F
authors.lastname: Gamboa
authors.forename: María Aránzazu
authors.initials: MA
authors.lastname: Martínez
authors.forename: Víctor
authors.initials: V
authors.lastname: Castellano
authors.forename: Marta
authors.initials: M
authors.lastname: Martínez
authors.forename: Irma
authors.initials: I
authors.lastname: Ares
authors.forename: Eva
authors.initials: E
authors.lastname: Ramos
authors.forename: Frank H
authors.initials: FH
authors.lastname: Suarez
authors.forename: María Rosa
authors.initials: MR
authors.lastname: Martínez-Larrañaga
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000097:blood / Q000493:pharmacokinetics*; D001682:Biological Availability; D002645:Chickens; D002751:Chlortetracycline / Q000097:blood / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D014018:Tissue Distribution
chemical_list: D000900:Anti-Bacterial Agents; D002751:Chlortetracycline