Comparative pharmacokinetics of cefquinome following intravenous and intramuscular administration in goats

The comparative pharmacokinetic profile of cefquinome following single intravenous (IV) and intramuscular (IM) administration of 2 mg/kg bodyweight was investigated in goats to determine the potential dosage regimen against susceptible microorganisms. Plasma concentrations of cefquinome were determined by high performance liquid chromatography. Plasma cefquinome disposition followed two-compartmental and mono-compartmental open models after IV and IM injection, respectively. Following IV injection, the major pharmacokinetic parameters (mean ± SEM) were t½α 1.17 ± 0.22 h, t1/2β 5.76 ± 0.19 h, Vd(area) 0.51 ± 0.05 L/kg, AUC 33.83 ± 2.53 μg /mL, ClB 0.06 ± 0.004 L/h/kg and MRT 6.09 ± 0.11 h. After IM administration, the principal pharmacokinetic parameters (mean ± SEM) were, Cmax 4.84 ± 0.23 μg/mL, Tmax 1.5 h, t½kα 0.64 ± 0.23 h, t½β 5.86 ± 0.29 h, AUC 19.82 ± 2.07 μg h/mL and MRT 8.08 ± 0.50 h. The bioavailability after IM injection was 57.39 ± 3.40%. A dosage regimen of 2 mg/kg body weight at 24 h interval following IV or IM injection would maintain the plasma levels required to be effective against the bacterial pathogens with MIC values ≤ 0.39 μg/mL.