Molecular characterization and susceptibility to antimicrobial drugs of isolated bacterials from shrimps (“Litopenaeus vannamei”)

Abstract

The objective was to isolate bacteria from gut of shrimps from Litopenaeus vannamei, by biochemical characterization and molecular identification, inhibition activity in vitro of Bacillus cereus and sensitivity pattern determination. The bacterial species isolated were: Aeromonas caviae (n = 7), Alcaligenes denitrificans (n = 1), Bacillus cereus (n = 1) and Enterobacter spp. (n = 3). Bacillus cereus isolated in this study did not have inhibitory activity to other shrimps isolated bacteria evaluated. In the susceptibility to antimicrobial drug test, it were observed 68,7% to erythromycin, 50% to tetracycline, 81,2% to trimethoprim:sulfamethoxazole, neomycin and estreptomycin, 12,5% to lincomycin and ampicillin, 87,5% to enrofloxacin and nitrofurantoin, 93,7% to ceftriaxone, 100% to norfloxacin and nalidix acid. The characterization molecular is important on identifying the microrganisms studied. The nalidixic acid and norfloxacin are antimicrobial drugs with high sensitivity for bacteria isolated from shrimps.