АНТИМИКРОБНАЯ АКТИВНОСТЬ ЭНРОФЛОКСАЦИНА IN VITRO

Abstract

Continuouse use of enrofloxacin contributes to emergence of enrofloxacin-resistant mi-crobial resistance, isolated and reported late-ly. In this study we deal with the spread of resistance of enrofloxacin among pathogenic organisms, infecting animals. The suscepti-bility to enrofloxacin was studied in standard disc diffusion assay. We studied 437 bacteri-al isolates in total. Salmonella dublin and Sal-monella typhimurium showed the highest suscepti-bility to enrofloxacin (100%); Salmonella enter-itidis and Salmonella choleraesuis proved a bit less susceptibility (95% and 94,7%). 5% of S. enter-itidis isolates and 5.3% of S. choleraesuis isolates had intermediate susceptibility. We did not register any resistance of isolates of Salmonella, Pasteurella and Morganella (Pasteurella multocida, Morganel-la morganii). 83.9% of Escherichiacoli strains proved susceptibility to enrofloxacin, the zone of retardation in 6.4% of the isolates was in corre-spondence with intermediate susceptibility, 9.7% of the isolates proved to be resistant. 90,9% of Pseudomonas aeruginosa isolates in our study was susceptible to enrofloxacin, 9.1% of them had intermediate susceptibility. The isolates of Strepto-coccus spp. and Staphylococcus pseudintermedius re-vealed high susceptibility to enrofloxacin, also as Listeria monocytogenes (causative agent of listeriosis)and Erysipe-lothrix rhusiopathiae (causative agent of swine erysipelas). 87.5% of the coagulase negative staphylococci proved susceptible to enrofloxacin; 6.25% of the isolates were resistant or had intermediate susceptibility. The shares of susceptible isolates of Staphylococcus hyicus, Staphylococ-cus aureus and Streptococcus uberis were respec-tively 65.1%, 75%, 75%. The shares of isolates with intermediate susceptibility of the same spp. were respectively 9.3%, 15%, 25%. The shares of resistant isolates of Staphylococci were respective-ly 25.6% and 10%. We found no strains of Str. uberis with resistance to enrofloxacin. As for Enterococci, 52.4% of the isolates were enrofloxacin-susceptible, 11,9% and 37,7% of them were re-spectively enrofloxacin-resistant or had intermedi-ate susceptibility. Presently most Gram-negative pathogenic bacteria have no resistance to enroflox-acin. Notwithstanding that enrofloxacin is signifi-cantly less effective against such pathogenic organ-isms as Staphylococci and Streptococci.