title: Pharmacokinetics and intramuscular bioavailability of amikacin in chickens following single and multiple dosing.
abstract: The pharmacokinetics of amikacin were studied in healthy mature female chickens (n = 6). Single doses of amikacin were injected as an i.v. bolus (10 mg/kg) and i.m. (20 mg/kg) into the same birds with a 30-day rest period between treatments. Amikacin was determined by the fluorescence polarization immunoassay method. The i.v. pharmacokinetics could be described by a two-compartment model with a t1/2 alpha of 0.150 +/- 0.064 h and a t1/2 beta of 1.44 +/- 0.34 h. The total body clearance was 0.109 +/- 0.017 1/h/kg and the volume of distribution at steady-state was 0.193 +/- 0.060 l/kg. Following a single i.m. injection, the peak plasma concentration (Cmax) was 50.79 +/- 4.05 micrograms/ml and occurred at 0.50 +/- 0.26 h. The i.m. extent of absorption was 91.2 +/- 17.6%. Simultaneous modeling of i.v. and i.m. results provided estimates of an absorption half-life of 0.480 +/- 0.158 h. The i.m. pharmacokinetics after repeated administration were studied following the tenth dose (20 mg/kg, every 8 h). The Cssmax was 38.58 +/- 6.96 micrograms/ml and occurred at 0.79 +/- 0.37 h, and the biological half-life of amikacin was 1.86 +/- 0.47 h. The multiple dosing yielded peak concentrations of 39 micrograms/ml and trough concentrations of 3.26 micrograms/ml. Based on these data, the recommended amikacin dosage in chickens is 20 mg/kg body weight every 8 h.
authors.affiliation: Animal Health Research Institute, Zagazig, Egypt.
authors.forename: A A
authors.initials: AA
authors.lastname: el-Gammal
authors.forename: W R
authors.initials: WR
authors.lastname: Ravis
authors.forename: L M
authors.initials: LM
authors.lastname: Krista
authors.forename: D S
authors.initials: DS
authors.lastname: Tolbert
authors.forename: A
authors.initials: A
authors.lastname: Saad
mesh_terms: D000042:Absorption; D000583:Amikacin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000818:Animals; D001682:Biological Availability; D002645:Chickens / Q000378:metabolism*; D005260:Female; D005454:Fluorescence Polarization; D006207:Half-Life; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D009132:Muscles / Q000378:metabolism*
chemical_list: D000583:Amikacin