Susceptibility profile of Pasteurella multocida and Mannheimia haemolytica samples isolated in the Botucatu’s region, São Paulo, Brazil, in the period from january 2000 to november 2007

Abstract

The antimicrobial therapy is still the tool of choice for control of infections caused by Pasteurella and Mannheimia species. This paper presents the results of antimicrobial susceptibility tests, performed by disk diffusion method, in 71 samples of Pasteurella multocida and 71 of Mannheimia haemolytica isolated from many species of animals coming from Botucatu’s region, São Paulo, Brazil, between January 2000 and November 2007. The results demonstrate large difference in susceptibility among the isolates, ranging from 74,54% (sulfa-trimethoprim) to 100,00% (ciprofloxacin and florfenicol), with regard to Pasteurella multocida, and from 80,05% (gentamicin) to 100,00% (ampicilin), with regard to Mannheimia haemolytica, in addition of the occurrence of multiple resistance. These data indicate the occurrence of resistant strains’ selection, due to the indiscriminate use of antimicrobial agents, and the importance of in vitro susceptibility test of pathogenic strains involved in clinical cases, to define the most appropriate antimicrobial therapy.