This study evaluated the antimicrobial sensitivity of 55 Salmonella strains from aquaculture facilities in Mato Grosso, Brazil. All strains showed complete sensitivity to 14 common antibiotics, and no clinically important serotypes were detected. The results highlight the necessity of continuous monitoring in aquaculture systems.
Literature Overview
The article 'Microbiological Monitoring and Microbial Susceptibility of Salmonella from Aquacultured Tambaqui Hybrids (Colossoma macropomum): Implications for Food Safety' published in the journal Antibiotics reviews the distribution and antimicrobial susceptibility of Salmonella strains in tambaqui aquaculture facilities in Mato Grosso, Brazil. Using the VITEK®2 Compact system, the study assessed minimum inhibitory concentrations (MICs) for 14 antimicrobial agents, classifying results according to Brazilian Committee on Antimicrobial Susceptibility Testing (BrCAST) standards. Findings revealed all strains were sensitive to tested antibiotics, with no detection of clinically significant serotypes such as S. Typhi or S. Paratyphi.
Background Knowledge
Salmonella is a globally significant foodborne pathogen, posing potential transmission risks in fish and aquaculture systems. Although fish are not natural hosts for Salmonella, its presence in aquatic environments raises food safety concerns. Recently, multidrug-resistant (MDR) Salmonella strains have become a priority for World Health Organization (WHO) surveillance due to associations with treatment failure, prolonged hospitalization, and increased mortality. This study, conducted in tambaqui aquaculture facilities in Mato Grosso, investigates serotypes and resistance patterns of Salmonella in farmed fish to inform food safety and public health policies.
Research Methods and Experiments
Researchers collected 72 tambaqui hybrid fish samples from 25 farms across eight cities in Mato Grosso (Cerrado and Pantanal biomes). Salmonella isolation and identification followed ISO 6579-1 standards, with strain confirmation via PCR amplification of the hilA gene. Subsequent serotyping and antimicrobial susceptibility testing employed the VITEK®2 Compact system, analyzing 14 commonly used antibiotics across multiple drug classes, including β-lactams, carbapenems, aminoglycosides, fluoroquinolones, and sulfonamides. All results were classified according to BrCAST criteria.
Key Conclusions and Perspectives
Research Significance and Prospects
This study demonstrates that Salmonella strains in tambaqui aquaculture under current management practices maintain susceptibility to common antibiotics, indicating low public health risk. However, continuous monitoring remains critical due to potential cross-contamination with livestock systems and resistance evolution. Future research should integrate serotyping with resistance gene analysis to comprehensively assess Salmonella transmission dynamics and public health impacts in aquaculture. Implementing One Health approaches could optimize antimicrobial stewardship by integrating data across human, animal, and environmental health domains.
Conclusion
Through systematic monitoring of Salmonella in tambaqui aquaculture facilities in Mato Grosso, Brazil, this study identified complete antimicrobial susceptibility among isolates and absence of clinically important serotypes. Nevertheless, persistent Salmonella presence highlights ongoing food safety concerns, particularly under changing environmental and management conditions. Antimicrobial use in aquaculture may drive resistance selection, necessitating future studies on microbial diversity and resistance evolution across production stages. The findings reinforce Brazil's zero-tolerance policy for Salmonella in fish products and provide scientific evidence for food safety and public health management frameworks.
