Antimicrobial susceptibility of Salmonella isolated from shrimp farms in Ceará State, Brazil

Abstract

The conventional use of antibiotics, particularly in intensive aquaculture systems, has led to the increase of microbial resistance through pathogen selection. This study tested the antimicrobial susceptibility of 23 Salmonella strains isolated from water, sediment and shrimp muscle, at four shrimp farms in Ceará State, Brazil. The tested sorovars to antimicrobials were: Salmonella Newport 14 (61%), Salmonella Anatum, 5 (22%), Salmonella Albany 3 (13%) and Salmonella Soahanina 1 (4%). Results showed the following resistance profiles: tetracycline - resistance of 35% and intermediate sensitivity of 61%; nalidix acid - resistance of 17%; and gentamicin - resistance of 4%. Multiresistance profile was observed in three (13%) sorovars of Salmonella Albany and one (4%) sorovar of Salmonella Newport. These results show an evidence of antibiotics indiscriminate use by shrimp farmers and how it can contribute to the raise of bacteria strains resistant to antimicrobials usually used as a treatment of human food poisoning.