title: In vivo antimicrobial activity of marbofloxacin against Pasteurella multocida in a tissue cage model in calves.
abstract: Marbofloxacin is a fluoroquinolone specially developed for use in veterinary medicine with broad-spectrum antibacterial activity. The objective of our study was to re-evaluate in vivo antimicrobial activity of marbofloxacin against Pasteurella multocida using subcutaneously implanted tissue cages in calves. Calves were infected by direct injection into tissue cages with P. multocida(type B, serotype 2), then intramuscularly received a range of marbofloxacin doses 24 h after inoculation. The ratio of 24 h area under the concentration-time curve divided by the minimum inhibitory concentration or the mutant prevention concentration (AUC24 h/MIC or AUC24 h/MPC) was the pharmacokinetic-pharmacodynamic (PK/PD) index that best described the effectiveness of marbofloxacin against P. multocida (R (2) = 0.8514) by non-linear regression analysis. Marbofloxacin exhibited a good antimicrobial activity in vivo. The levels of AUC24 h/MIC and AUC24 h/MPC that produced 50% (1.5log10 CFU/mL reduction) and 90% (3log10 CFU/mL reduction) of maximum response were 18.60 and 50.65 h, 4.67 and 12.89 h by using sigmoid Emax model WINNONLIN software, respectively. The in vivo PK/PD integrated methods by tissue cage model display the advantage of the evaluation of antimicrobial activity and the optimization of the dosage regimen for antibiotics in the presence of the host defenses, especially in target animal of veterinary interest.
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Changfu
authors.initials: C
authors.lastname: Cao
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Qu
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Meizhen
authors.initials: M
authors.lastname: Sun
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Zhenzhen
authors.initials: Z
authors.lastname: Qiu
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Xianhui
authors.initials: X
authors.lastname: Huang
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Binbin
authors.initials: B
authors.lastname: Huai
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Lu
authors.affiliation: National Reference Laboratory of Veterinary Drug Residues, College of Veterinary Medicine, South China Agricultural University Guangzhou, China ; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University Guangzhou, China.
authors.forename: Zhenling
authors.initials: Z
authors.lastname: Zeng
keywords: Pasteurella multocida; calves; in vivo antimicrobial activity; marbofloxacin; tissue cage model