Pharmacokinetics of a single intramuscular injection of cefquinome in buffalo calves.

The objective of this study was to investigate the pharmacokinetics of cefquinome following single intramuscular (IM) administration in six healthy male buffalo calves. Cefquinome was administered intramuscularly (2 mg/kg bodyweight) and blood samples were collected prior to drug administration and up to 24 hr after injection. No adverse effects or changes were observed after the IM injection of cefquinome. Plasma concentrations of cefquinome were determined by high-performance liquid chromatography. The disposition of plasma cefquinome is characterized by a mono-compartmental open model. The pharmacokinetic parameters after IM administration (mean ± SE) were Cmax 6.93 ± 0.58 µg/ml, Tmax 0.5 hr, t½kα 0.16 ± 0.05 hr, t½ß 3.73 ± 0.10 hr, and AUC 28.40 ± 1.30 µg hr/ml after IM administration. A dosage regimen of 2 mg/kg bodyweight at 24-hr interval following IM injection of cefquinome would maintain the plasma levels required to be effective against the bacterial pathogens with MIC values ≤0.39 µg/ml. The suggested dosage regimen of cefquinome has to be validated in the disease models before recommending for clinical use in buffalo calves.