二氟沙星对实验性感染猪支原体性肺炎及链球菌病的药效学研究

Pharmacodynamic Studies of Difloxacin against Experimentally Induced Mycoplasmal Pneumonia and Streptococcosis in Pigs

以试管两倍稀释法测得二氟沙星对猪肺炎支原体（ Ｆ１６ 株）和兰氏 Ｃ 群类马链球菌（ Ｃ５５ １ ２０ ）的最小抑菌浓度分别是０１６ｍ ｇ／ Ｌ及 １６ｍ ｇ／ Ｌ。肌注给药对猪支原体性肺炎及链球菌病的实验性治疗结果表明，低、中、高剂量二氟沙星组（２５、５、１０ｍ ｇ／ｋｇ）及蒽诺沙星组（２５ｍ ｇ／ｋｇ）用药 ５ 天（每隔 １２ 小时给药一次）对猪支原体性肺炎的治愈率分别是 ８０％ 、９０％ 、１００％ 及９０％ ；而支原体感染对照组的自愈率为１０％ 。低、中、高剂量二氟沙星组及蒽诺沙星组（２５ｍ ｇ／ｋｇ）用药 ４ 天（每隔 １２ 小时给药一次）对猪链球菌病的治愈率分别是 ５０％ 、８０％ 、８０％ 及 ８０％ ，而链球菌感染对照组的死亡率为 ５０％ 。

This paper described the pharmacodynamic studies of difloxacin and enrofloxacin against experimentally induced mycoplasmal pneumonia and streptococcosis in pigs.Minimal inhibitory concentrations (MICs) of the two drugs were determined for Mycoplasma hyopneumoniae or Streptococcus equisilis by two-fold dilution method in vitro.The therapeutic trials of difloxacin (2.5,5 and 10 mg/kg)and enrofloxacin (2.5 mg/kg) against artificially induced mycoplasmal pneumonia were performed in pigs following intramuscular administration,twice daily for 5 successive days.The therapeutic trials of difloxacin (2.5,5 and 10 mg/kg) and enrofloxacin (2.5 mg/kg) against experimentally induced streptococcosis were carried out in pigs following intramuscular administration,twice daily for 4 successive days.MICs of difloxacin and enrofloxacin were 0.16 and 0.04 mg/L for Mycoplasma hyopneumoniae,respectively.MICs of difloxacin and enrofloxacin were 1.6 and 0.8mg/L for Streptococcus equisimilis,respectively.Following the treatment with difloxacin (2.5,5 and 10 mg/kg) and enrofloxacin (2.5 mg/kg)against mycoplasmal pneumonia for 5 days,the curative rates of the infected pigs were 80%,90%,100% and 90%,respectively.The self curative rate of the infected and untreated group was 10%.Following the treatment with difloxacin (2.5,5 and 10 mg/kg) and enrofloxacin (2.5 mg/kg)against streptococcosis for 4 days,the curative rates of the infected pigs were 50%,80%,80% and 80%,respectively.The mortality of the infected and untreated group was 50%.