In vitro susceptibility of resistant Escherichia coli field isolates to antimicrobial combinations

• DOI: 10.3382/japr.2011-00500
• Publication Date: 2012-08-09T20:34:36Z
• Authors: E.A. Abu-Basha; S.M. Gharaibeh; A.M. Thabet
• Keywords: Florfenicol; Spectinomycin; Fosfomycin

Avian colibacillosis is an infectious disease of chickens caused by avian pathogenic Escherichia coli (APEC). Respiratory viruses and Mycoplasma infections cause damage to the respiratory system predispose them APEC. The APEC field isolates have begun showing increased antimicrobial resistance, leading failure treatment increasing costs production losses. objective this study was investigate susceptibility different combinations using minimum inhibitory concentration checkerboard tests. All 18 were resistant amoxicillin, clavulanic acid, doxycycline, oxytetracycline, erythromycin, whereas 71 76% these ciprofloxacin enrofloxacin, respectively. Fosfomycin had best activity against isolates, followed gentamicin, spectinomycin, florfenicol, with percentages 35, 41, 47, 53%, A total 46 antibiotic used test each E. isolate technique. On basis results for synergistic partial activities, amoxicillin-clavulanic ciprofloxacin-fosfomycin, oxytetracycline-erythromycin, oxytetracycline-florfenicol, amoxicillin-gentamicin, oxytetracycline-spectinomycin, spectinomycin-erythromycin in vitro antimicrobials, activities more than 80% isolates. Further vivo studies are needed correlate efficacy reduce economic losses poultry industry.