Biogeography of Kudoa spp. (Myxosporea: Multivalvulida) distributed in Asian Seas with special reference to risk management of Kudoa food poisoning

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K05995
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 42020:Veterinary medical science-related
• Research Institution: Yamaguchi University
• Principal Investigator: Sato Hiroshi 山口大学, 共同獣医学部, 教授 (90211945)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: クドア食中毒 / 多殻目粘液胞子虫 / 海産魚 / 種多様性 / Kudoa / Unicapsula / rDNA / 生物地理学

Outline of Final Research Achievements

After identification of Kudoa septempunctata as the cause of outbreaks of new food poisoning after consumption of fresh olive flounder, named 'Kudoa food poisoning', K. hexapunctata in the Thunnus tunas, K. iwatai in the sea bass, and Unicapsula seriolae in the greater amberjack have been added as potential causes of Kudoa food poisoning. However, identification of multivalvulid species of the genera Kudoa and Unicapsula is hampered by the paucity of taxonomic and biogeographical knowledgement of the multivalvulids. This study collected a variety of Kudoa spp. and Unicapsula spp. from commercial marine fishes in the waters around Japan and China, and characterized individually their morphological and molecular-genetic data as taxonomic units. Accumulation of rDNA nucleotide sequences of variable multivalvulid species with taxonomic reliability enables feasible identification of the cause of Kudoa food poisoning.

Free Research Field

獣医寄生虫学

Academic Significance and Societal Importance of the Research Achievements

本研究では日本近海、ベーリング海、南シナ海、ジャワ海、大西洋に生息する市販海産魚に寄生する多殻目粘液胞子虫について調べ、既知種13種、新種11種を検出するとともに、胞子の形態学的観察とrDNAならびにmtDNA塩基配列情報を集積した。クドア食中毒の原因となり、また、養殖現場で重要な寄生虫病となる多殻目粘液胞子の種多様性の把握とDNA情報の集積は、食品衛生あるいは養殖現場、検疫現場での種同定において重要な基盤情報となる。本研究で得られた成果は、論文あるいはDNA公開リポジトリDDBJ等で公開している。