Antibacterial efficacy and pharmacokinetic studies of ciprofloxacin on Pasteurella multocida infected rabbits

Twenty four isolates of Pasteurella multocida were taken from 74 diseased rabbits which suffered from respiratory manifestations with an incidence 35.1%. All isolated strains were identified biochemically and serologically as Pasteurella multocida type 3. The in vitro sensitivity test proved that Ciprofloxacin was the most effective antibiotic which was used for treatment of diseased rabbits. There was no isolation of Pasteurella multocida organism from all treated rabbits with Ciprofloxacin which can eliminate the causative organism, and control the infection within the examined rabbit colony. The kinetics of Ciprofloxacin, a fluoroquinolone, was studied after multiple oral and I/V dose of 20 mg/kg b. wt. In healthy rabbits and in those diseased with Pasteurella multocida Ciprofloxacin was given at a dose (20 mg kg-1/day) orally for successive 5 days. Serum levels reached their peak Tmax, at 2.321 and 2.524 hrs. in healthy and infected rabbits after oral administration, with absorption half-life (t0.5 (ab)) of 1.22 and 2.41 hrs. and elimination half-life (t0.5 (B)) of 2.24 and 1.28 hour respectively. Following I/V injection the kinetics of Ciprofloxacin follow two compartment model with (t0.5 (B)) 1.201 and 0.82 hour for normal and infected rabbits, (Vd (area)) of 0.653 and 0.563 L/kg and total body clearance CL(B) of 0.385 and 0.358 L/kg/hr respectively. High tissue concentrations of the drug were recorded in the kidneys, lung, spleen, liver, and muscle of diseased rabbits, while in healthy animal group the highest concentrations were achieved in kidney, liver, lung, spleen, and muscle. The high Ciprofloxacin tissue concentrations indicate that the Ciprofloxacin may be an excellent drug for treating urinary and respiratory tract infections.