Sujan Khadka
Research
Recirculating aquaculture systems (RAS) hold promise in meeting global fish demands and have been increasingly utilized in Norway to produce Atlantic salmon smolts. RAS constitutes a complex bacterial ecosystem, often dominated by fast-growing opportunistic heterotrophs. These heterotrophs can adversely affect fish health, welfare, and survival, compromising sustainable fish production. Effective system design and operational management can enhance fish welfare by mitigating the persistence and proliferation of heterotrophs. However, our understanding of bacterial management in RAS remains limited. To improve the knowledge in bacterial management of RAS, my PhD research aims to:
- Investigate the qualitative and quantitative assessment of bacterial origins and their impacts on various land-based rearing systems for marine fish larvae.
- Examine the role of biofilter-biofilm microbiota in structuring the microbiota of Atlantic salmon and rearing water in RAS.
- Analyze the effects of smoltification and increasing salinity on the intestinal, skin, and gill microbiomes of Atlantic salmon in RAS under varying particle loads.
- Explore the comparative effects of cork and commercial feed on structuring water, biofilm carriers, and gut microbiota of Atlantic salmon.
RASOPTA (Safeguarding future production of fish in aquaculture systems with water recirculation)
The main goals of RASOPTA centre around filling in the existing knowledge voids within the European fish production sector, particularly focusing on species crucial for human nutrition and the economy.
Analysis and Control of Microbial Systems (ACMS) Group
Analysis of microbial systems represents a field of science denoted microbial ecology and environmental biotechnology.
Publications
Electric stimulation: a versatile manipulation technique mediated microbial applications
This review article summarizes recent advancements in ES and discusses it as a unique external manipulation technique for microorganisms with wide applications in bioremediation, industry, biofilm deactivation, disinfection, and controlled biosynthesis.
Bacteria in land-based larval rearing systems: sources of bacteria and their quantitative and qualitative influence on the microbiota of rearing water and larvae
This study is the first to create a bacterial budget across different larval-rearing systems. It highlights how rearing technology strongly influences microbial exposure to the larvae, offering new insights for microbial management strategies.
Biofilter performance, water quality, and microbial dynamics in RAS operated under high or low suspended solids load
The results of this study indicate the potential impacts of accumulating organic matter on RAS water quality, microbiota, and fish performance.