Hints for efficient feeding methods for the leopard coral grouper


August 24, 2017

Toward low environmental-load aquaculture based on metabolic marker information

The leopard coral grouper(Plectropomus leopardus) is one of three types of value added Asian fish commercially distributed in Okinawa. Aquaculture technology of this species is established by the Japan Fisheries Research and Education Agency (FRA) , but feeding methods have yet to be optimized, resulting in slow growth with excess visceral fat. To achieve efficiently cultivate healthy and tasty fishes, scientific evidences are needed to help determine ideal feeding methods such as total amounts and feed timing.

As a step toward this goal, RIKEN CSRS and FRA have succeeded in extracting metabolic marker information from the leopard coral grouper. The joint research team carried out a detailed analysis of metabolic changes in the leopard coral grouper that occur due to feeding. Using a non-targeted analysis combining transcriptome analysis by next-generation sequencing and metabolome analysis by NMR, researchers found two types of metabolic marker information: for short-term metabolism changes in conjunction with the fish's circadian rhythm and slow metabolism changes associated with fasting and feeding. For the short-term metabolism associated with circadian rhythm, the concentration of basic metabolites responsible for energy production such as nucleic acid substances and the citric acid cycle fluctuated. Meanwhile, the responses to changes in the order of feeding showed expression of the genes associated with energy accumulation and fluctuation in the concentration of branched chain amino acids such as leucine.

These results are expected to contribute to the development of efficient leopard coral groupert feeding methods based on these two metabolic rhythms and aquacultue with low environmentalloads by reducing excess feed.

Original article
Scientific Reports doi:10.1038/s41598-017-09531-4
M. Mekuchi, K. Sakata, T. Yamaguchi, M. Koiso, J. Kikuchi,
"Trans-omics approaches used to characterise fish nutritional biorhythms in leopard coral grouper (Plectropomus leopardus)".
Jun Kikuchi; Team Leader
Kenji Sakata; Technical Staff
Environmental Metabolic Aanalysis Research Team