Fecal diagnosis for fish feces

June 18, 2024

Identifying non-invasive biomarkers detecting fish disease from on-shore aquaculture

The National Institute of Advanced Industrial Science and Technology (AIST) collaborating with the RIKEN CSRS and Kindai University found various distinct compounds and microbes in feces of fish with bacterial cold-water disease. They also revealed that these findings can be used as biomarkers for early detection of infection.

Taking advantage of AIST’s microbiome analysis technology, RIKEN’s metabolomic analysis technology, and Kindai University’s technique for fish infection challenge tests, they conducted metabolomic and metagenomic analyses of fish feces. And for the first time, they successfully identified metabolites and microbes specific to fish with bacterial cold-water disease in feces accumulated in a tank. Bacterial cold-water disease is causing severe damage to some freshwater fish, such as sweetfish or Ayu (Plecoglossus altivelis) and rainbow trout (Oncorhynchus mykiss) around the world. Early detection of this disease is crucial as there are no preventive measures, including vaccines, against it. Analyzing feces will allow us to diagnose disease noninvasively without removing tissues from fish, as is currently done, and to monitor fish health on a regular and holistic basis. The findings of this study suggest several possible biomarkers for those purposes. The researchers expect that, in the future, the technology that they have developed in this study can be used for early detection of various fish diseases in addition to bacterial cold-water disease and simple fish health monitoring. The group hopes that this technology will contribute to reducing economic loss and environmental burden caused by fish disease.

Original article: mSphere doi: 10.1128/msphere.00301-24; M. Takeuchi, E. Fujiwara-Nagata, K. Kuroda, K. Sakata, T. Narihiro, J. Kikuchi,; "Fecal metagenomic and metabolomic analyses reveal non-invasive biomarkers of Flavobacterium psychrophilum infection in ayu (Plecoglossus altivelis)".
Contact: Jun Kikuchi
Team Leader
Environmental Metabolic Analysis Research Team