Optimizing the Dosage of Ceftiofur to Treat Porcine Respiratory Infection Based on a Population Pharmacokinetic Model and Monte Carlo Simulation

Porcine respiratory diseases is a major cause of economic losses in livestock, and ceftiofur is one of the core therapeutic agents for its treatment, but the clinical efficacy can be inconsistent. Therefore, it is necessary to utilize a population pharmacokinetic model to reveal the distribution and metabolic patterns of ceftiofur in pig populations, while also combining Monte Carlo simulation techniques to predict the probability of treatment success under different dosing regimens. To investigate the probability of attaining the pharmacokinetic/pharmacodynamic targets of ceftiofur in pigs infected with different respiratory bacteria, a population pharmacokinetic model for the intramuscular administration of ceftiofur in pigs was developed, and Monte Carlo simulation was performed to analyze the target attainment rate of ceftiofur at different doses. The results showed that the target attainment rate of ceftiofur was 100% for Pasteurella multocida at the dose of 0.5 mg/kg b.w. intramuscularly, 99.9% for Actinobacillus pleuropneumoniae at 1 mg/kg b.w. intramuscularly, 93.4% for Streptococcus suis at 0.5 mg/kg b.w. intramuscularly, and 95.4% for Haemophilus parasuis at 10 mg/kg b.w. intramuscularly. The results indicate that it is crucial to optimize the dosage based on specific infected bacteria to improve the success rate of treatment and extend the clinical application period of ceftiofur.