Assessment of antimicrobial resistance profiles in fish farms using shared groundwater sources

Abstract

The indiscriminate use of antimicrobials in aquaculture is a concerning practice due to the risk of spreading drug-resistant bacterial strains. This study aimed to assess the bacterial resistance profile in water sourced from a fish farming supply located in Buriti dos Lopes, Piauí, Brazil. Bacterial counts for the P1 supply point reached 6.5 log CFU/mL, while counts ranged from 3.31 to 3.66 log CFU/mL at Farm A (FA) and 2.56 to 2.79 log CFU/mL at Farm B (FB). Among the 40 strains (67.8%) tested for antimicrobial resistance, resistance was observed to quinolone (15.25%), first-generation cephalosporins (16.95%), third-generation cephalosporins (35.6%), aminopenicillin (30.51%), sulfonamide (8.47%), and carbapenem (1.7%). Similarity analysis revealed a resistance profile similarity of over 85% between isolates from P1-FA and P1-FB, suggesting the water source significantly influences the spread of resistance. Alarmingly, bacterial strains exhibiting multiple antimicrobial resistances were found in the groundwater supplying fish farms. Therefore, investigating the dissemination of phenotypic and genotypic resistance profiles is crucial to informing public policies that address the impacts of indiscriminate drug use and its environmental dissemination.