title: Pharmacokinetics of ceftiofur crystalline free acid after single and multiple subcutaneous administrations in healthy alpacas (Vicugna pacos).
abstract: Six adult male alpacas received one subcutaneous administration of ceftiofur crystalline free acid (CCFA) at a dosage of 6.6 mg/kg. After a washout period, the same alpacas received three subcutaneous doses of 6.6 mg/kg CCFA at 5-day intervals. Blood samples collected from the jugular vein before and at multiple time points after each CCFA administration were assayed for ceftiofur- and desfuroylceftiofur-related metabolite concentrations using high-performance liquid chromatography. Pharmacokinetic disposition of CCFA was analyzed by a noncompartmental approach. Mean pharmacokinetic parameters (± SD) following single-dose administration of CCFA were Cmax (2.7 ± 0.9 μg/mL); Tmax (36 ± 0 h); area under the curve AUC0→∞ (199.2 ± 42.1 μg·h/mL); terminal phase rate constant λz (0.02 ± 0.003/h); and terminal phase rate constant half-life t1/2λz (44.7 h; harmonic). Mean terminal pharmacokinetic parameters (±SD) following three administrations of CCFA were Cmax (2.0 ± 0.4 μg/mL); Tmax (17.3 ± 16.3 h); AUC0→∞ (216.8 ± 84.5 μg·h/mL); λz (0.01 ± 0.003/h); and t1/2λz (65.9 h; harmonic). The terminal phase rate constant and the Tmax were significantly different between single and multiple administrations. Local reactions were noted in two alpacas following multiple CCFA administrations.
authors.affiliation: Departments of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Dechant
authors.forename: J D
authors.initials: JD
authors.lastname: Rowe
authors.forename: B A
authors.initials: BA
authors.lastname: Byrne
authors.forename: S E
authors.initials: SE
authors.lastname: Wetzlich
authors.forename: H T
authors.initials: HT
authors.lastname: Kieu
authors.forename: L A
authors.initials: LA
authors.lastname: Tell
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001419:Bacteria / Q000187:drug effects; D002161:Camelids, New World / Q000378:metabolism*; D002511:Cephalosporins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004334:Drug Administration Schedule; D006207:Half-Life; D007279:Injections, Subcutaneous / Q000662:veterinary; D008297:Male; D008826:Microbial Sensitivity Tests
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; C053503:ceftiofur