Introduction
Catfish aquaculture plays an increasingly important role in food security, rural livelihoods, and value-added fish processing in Southeast Asia. However, intensification of catfish production has raised One Health concerns due to the combined emergence of antimicrobial-resistant bacteria and environmental contaminants, particularly heavy metals, which may affect aquatic animal health, food safety, consumer health, and surrounding ecosystems. In Thailand, clariid catfish are widely consumed and are also processed into fermented fish products that support local economies. Nevertheless, aquaculture water, fish tissues, and post-harvest processing chains may serve as reservoirs and transmission interfaces for pathogenic bacteria, antimicrobial resistance (AMR), virulence factors, and chemical contaminants. This study presents an integrated One Health framework to evaluate antimicrobial resistance, virulence-associated bacteria, and heavy metal-related risks in clariid catfish aquaculture and fermented fish production systems.
Materials and Methods
Fish and water samples associated with clariid catfish aquaculture and fermented catfish production were collected from production areas in Thailand. Bacterial isolation was performed using selective culture media targeting Escherichia coli, Salmonella spp., and Vibrio cholerae. Antimicrobial susceptibility testing was conducted using the disk diffusion method against nine antibiotics, and multidrug resistance profiles were assessed. Polymerase chain reaction (PCR) was used to detect selected antimicrobial resistance genes and virulence genes. To broaden the One Health interpretation, available evidence on heavy metal contamination in hybrid catfish aquaculture systems was integrated with environmental risk concepts, including water quality, tissue bioaccumulation, oxidative stress biomarkers, transcriptional responses, and human health risk assessment.
Results
Bacterial isolates, including E. coli, Salmonella spp., and V. cholerae, were detected in clariid catfish and water samples associated with fermented fish production. Antimicrobial susceptibility testing revealed diverse resistance patterns, with multidrug resistance observed particularly among E. coli and Salmonella spp. The resistance profiles were mainly associated with β-lactam and tetracycline antibiotics, suggesting potential selective pressure from antimicrobial use and environmental contamination. Molecular assays confirmed the presence of antimicrobial resistance genes and virulence-associated genes among bacterial isolates, suggesting that catfish production environments may function as reservoirs of foodborne and antimicrobial-resistant bacteria. In parallel, evidence from heavy metal risk assessment in catfish aquaculture demonstrated that canal-specific environmental contamination can drive metal bioaccumulation, oxidative stress, altered expression of detoxification and immune-related genes, and elevated non-carcinogenic and carcinogenic health risks at contamination hotspots.
Discussion
These findings support the view that AMR and heavy metal contamination should not be treated as separate problems in aquaculture, but rather as interconnected One Health pressures linking aquatic environments, farm management, fish health, food processing, and consumer safety. The detection of antimicrobial-resistant and potentially virulent bacteria in clariid catfish and water used for fermented fish production highlights the need for continuous microbiological surveillance, responsible antimicrobial use, and improved biosecurity. At the same time, heavy metal bioaccumulation and molecular stress responses emphasize the importance of environmental monitoring beyond farm-level certification, particularly where aquaculture systems rely on canal networks influenced by urban, agricultural, or industrial land use. An integrated One Health surveillance platform combining AMR monitoring, virulence gene detection, heavy metal assessment, and environmental risk mapping would strengthen food safety management and support the sustainable development of catfish aquaculture and fermented fish value chains.
Catfish; One Health; antimicrobial resistance; heavy metals; food safety
Acknowledgment
This study was supported by the Program Management Unit on Area Based Development (PMU-A) (Contract No. A11F680039; the Program Management Unit for Human Resources and Institutional Development, Research and Innovation (PMU-B) under Contract No. B13F670053; the Program Management Unit for Competitiveness (PMU-C), through the Global Partnership Program, under Contract No. C23F670224; the National Research Council of Thailand (NRCT) through the High-Potential Research Team Grant Program under Contract No. N42A660605; Betagro Group under Grant No. 6501.0901.1/68; the Kasetsart University Research and Development Institute under Grant No. FF(KU)61.69; and the International SciKU Branding (ISB) initiative of the Faculty of Science, Kasetsart University.
References
Shahi, M. K., Odoi, J. O., Anuntawirun, S., Roongrojmongkhon, N., Singchat, W., Panthum, T., Prasanpan, J., Griffin, D. K., Srikulnath, K., & Jeamsripong, S. (2025). Antimicrobial resistance in global catfish aquaculture: Trends, control strategies, and public health implications. Aquaculture, 605, Article 742552. https://doi.org/10.1016/j.aquaculture.2025.742552
Uno, U., Singchat, W., Panthum, T., Chaiyes, A., Ekerette, E., Edem, U., Jeamsripong, S., Uchuwittayakul, A., Sirisaksoontorn, W., Sinthuvanich, C., & Srikulnath, K. (2026). Spatial Land Use Dynamics Driving Molecular Stress and Unacceptable Human Health Risks in Standardized Catfish Aquaculture Systems. Environments, 13(4), 231. https://doi.org/10.3390/environments13040231