Identification of Massive Fish Eggs for Spawning Ecology and eDNA Analysis for Macro Aquatic Fauna using Metabarcoding

Abstract

Metabarcoding is a very useful technique searching for species by comparing the high-throughput DNA sequence reads obtained from NGS (next generation sequencing) to the DNA barcode reference library. Using this method, it is not only possible to find spawning season and area of various fishes from massive mixed fish eggs, but to study the species diversity of macro aquatic fauna from environmental DNA (eDNA). Only the way to collect samples is different between the two kinds of research fields, but the process of metacoding based on the NGS analysis is almost same. I will introduce you representative research cases using metabarcoding tool in both fields . For the spawning ecology of teleost fishes, it is very important to know the egg distribution identified as species levels. This is because the egg is direct evidence of the spawning season and area of various fishes in vast ocean. Most teleost fish eggs are spherical with a diameter of about 1.0 mm, and are not able to be identified at species level except for some oceanic fishes. Therefore, the research for the spawning ecology using the fish eggs is very limited worldwide. Recently, searching for spawning sites using the fish eggs identified by molecular markers is increasing. A representative example is the discovery of wild eel’s eggs analyzed by Sanger sequencing (SS). Nevertheless, there are still very few cases of spawning ecology based on the fish eggs. le to find spawning season and area of various fishes from massive mixed fish eggs, but to study the species diversity of macro aquatic fauna from environmental DNA (eDNA). Only the way to collect samples is different between the two kinds of research fields, but the process of metacoding based on the NGS analysis is almost same. I will introduce you representative research cases using metabarcoding tool in both fields . For the spawning ecology of teleost fishes, it is very important to know the egg distribution identified as species levels. This is because the egg is direct evidence of the spawning season and area of various fishes in vast ocean. Most teleost fish eggs are spherical with a diameter of about 1.0 mm, and are not able to be identified at species level except for some oceanic fishes. Therefore, the research for the spawning ecology using the fish eggs is very limited worldwide. Recently, searching for spawning sites using the fish eggs identified by molecular markers is increasing. A representative example is the discovery of wild eel’s eggs analyzed by Sanger sequencing (SS). Nevertheless, there are still very few cases of spawning ecology based on the fish eggs.