Andrew Mead, Abigail Hughes, Stefano Azzariti, Pierre-Louis Toutain, Ludovic Pelligand
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引用次数: 0
Abstract
This study examines the pharmacodynamics (PD) of florfenicol (FFN) for treating porcine respiratory diseases by comparing its effects on Glaesserella parasuis, Actinobacillus pleuropneumoniae and Pasteurella multocida. In vitro time-kill assays and semi-mechanistic PD modeling were used to assess bacterial growth and killing rates at varying FFN concentrations. Species-specific PD models indicated that fAUC/MIC was the best PK/PD index across all species. A. pleuropneumoniae and P. multocida had target values of 1.05 and 1.66 × MIC, respectively for bacteriostasis and 1.12 and 1.87 × MIC for 99.9% kill. Two phenotypes of G. parasuis emerged "fast-kill" and "slow-kill" which displayed distinct bacterial eradication rates despite similar MICs. For "slow-kill" isolates, an average free drug concentration (fAUC/MIC) of 1.46 and 1.63 × MIC (median, range: 1.53-1.69) was required for bacteriostasis and 99.9% kill. "Fast-kill" isolates needed an average free drug concentration of 1.38 × MIC for bacteriostasis and 1.51 × MIC for a 99.9% reduction. Indicating that the rate of kill influences the respective average free concentration required to achieve an equivalent antibacterial effect. Simulations of clinical dosing of FFN predicted bacterial eradication for all species, highlighting the value of phenotype-specific PD modeling in guiding treatment strategies for porcine respiratory infections.
期刊介绍:
The Journal of Veterinary Pharmacology and Therapeutics (JVPT) is an international journal devoted to the publication of scientific papers in the basic and clinical aspects of veterinary pharmacology and toxicology, whether the study is in vitro, in vivo, ex vivo or in silico. The Journal is a forum for recent scientific information and developments in the discipline of veterinary pharmacology, including toxicology and therapeutics. Studies that are entirely in vitro will not be considered within the scope of JVPT unless the study has direct relevance to the use of the drug (including toxicants and feed additives) in veterinary species, or that it can be clearly demonstrated that a similar outcome would be expected in vivo. These studies should consider approved or widely used veterinary drugs and/or drugs with broad applicability to veterinary species.