Parameter Unit Mean ± SD Log E0 Cfu/mL 2.39 ± 0.09 Log Emax Cfu/mL -4.51 ± 0.11 Log Emax - E0 Cfu/mL -6.91 ± 0.16 AUC24h/MIC for bacteriostatic action h 32.13 ± 2.05 AUC24h/MIC EC50 h 36.24 ± 1.01 AUC24h/MIC for bactericidal action h 47.15 ± 4.72 AUC24h/MIC for bacterial eradication h 60.96 ± 3.85 Slope (N) - 4.859 ± 0.71 E0: difference in bacterial count in control sample (without drug) between time 0 and 24 h; Emax: difference in bacterial count in sample incubated with gentamicin between time 0 and 24 h, when the detection limit is reached; AUC24h/MIC EC50: AUC24h/MIC of drug producing 50% of the maximum antibacterial effect; N: slope of the AUC24h/MIC - response curve.

Table 3: PK– PD modeling of gentamicin against P. multocida using in vitro serum data in buffalo calves.