Study on impact and pathobiology of Perkinsus infection in wild Manila clam for recovery of Manila clam resources

• Project/Area Number: 22380106
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: General fisheries
• Research Institution: The University of Tokyo
• Principal Investigator: YOSHINAGA Tomoyoshi 東京大学, 大学院・農学生命科学研究科, 教授 (20345185)
• Project Period (FY): 2010 – 2012
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥19,760,000 (Direct Cost: ¥15,200,000、Indirect Cost: ¥4,560,000); Fiscal Year 2012: ¥5,720,000 (Direct Cost: ¥4,400,000、Indirect Cost: ¥1,320,000); Fiscal Year 2011: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2010: ¥8,840,000 (Direct Cost: ¥6,800,000、Indirect Cost: ¥2,040,000)
• Keywords: アサリ / Perkinsus / 病害 / 資源 / 原虫 / 野生集団 / 減耗要因 / パーキンサス

Research Abstract

Experimental challenge of Manila clam with the protozoan Perkinsus olseni revealed that this protozoan was lethal to the host and that the lethal infection intensity to Manila clam was around 106 cells/g soft tissue weight. Three-year monitoring of the infection level of the protozoan and the dynamics of a host population was carried out at one location in Ariake Bay where Manila clam population has dramatically decreased since late 1970s. This monitoring demonstrated that the infection prevalence reached 100 % and the population sizes of Manila clams decreased when the highest infection intensities reached the lethal infection intensity experimentally obtained. The results strongly suggested that infection with the protozoa was the major factor for the depletion of Manila clam resources.

Research Products

• [Journal Article] Effects of temperature and salinity on the in vitro proliferation of trophozoites and the development of Zoosporangia in Perkinsus olseni and P. honshuensis, both Infecting Manila clam (2013)
  • Author(s): Umeda, K., Shimokawa, J., Yoshinaga, T
  • Journal Title: Fish Pathology Volume: 48 Pages: 13-16
  • NAID: 10031162769
  • Peer Reviewed
• [Journal Article] Effects of Temperature and Salinity on the in vitro Proliferation of Trophozoites and the Development of Zoosporangia in Perkinsus olseni and P. honshuensis, Both Infecting Manila clam. (2013)
  • Author(s): Umeda, K., Shimokawa, J., Yoshinaga,
  • Journal Title: Fish Pathology Volume: 48(1) Pages: 13-16
  • NAID: 10031162769
  • Peer Reviewed
• [Journal Article] Development of real-time PCR assays for two Perkinsus spp. in the Manila clam Ruditapes philippinarum (2012)
  • Author(s): Umeda, K., Yoshinaga, T
  • Journal Title: Diseases of Aquatic Organisms Volume: 99 Pages: 215-225
  • Peer Reviewed
• [Journal Article] Experimental challenges of wild Manila clams with Perkinsus species isolated from naturally infected wild Manila clams (2012)
  • Author(s): Waki, T., Shimokawa, J., Watanabe, S., Yoshinaga, T., Ogawa, K
  • Journal Title: Journal of Invert.Pathology Volume: 111 Pages: 50-55
  • Peer Reviewed
• [Journal Article] Development of real-time PCR assays for two Perkinsus spp. in the Manila clam Ruditapes philippinarum (2012)
  • Author(s): Umeda, K., Yoshinaga, T.
  • Journal Title: Diseases of Aquatic Organisms Volume: 99(3) Issue: 3 Pages: 215-225
  • DOI: 10.3354/dao02476
  • Peer Reviewed
• [Presentation] 有明海定点におけるPerkinsus属原虫のアサリの減耗への関与 (2013)
  • Author(s): 脇司・良永知義
  • Organizer: 平成25年度日本水産学会春季大会
  • Place of Presentation: 東京
  • Year and Date: 2013-03-26
• [Presentation] アサリのPerkinsus属原虫の分布に影響する環境要因について (2013)
  • Author(s): 梅田剛佑・高橋美希・脇司・悦喜達也・良永知義
  • Organizer: 平成25年度日本水産学会春季大会
  • Place of Presentation: 東京
  • Year and Date: 2013-03-26
• [Presentation] アサリに寄生するPerkinsus属原虫2種の国内分布 (2013)
  • Author(s): 梅田剛佑・良永知義
  • Organizer: 平成25年度日本魚病学会春季大会
  • Place of Presentation: 東京
  • Year and Date: 2013-03-09
• [Presentation] アサリに寄生するPerkinsus属原虫の病害性の実験的な評価 (2013)
  • Author(s): 脇司・良永知義
  • Organizer: 平成25年度日本水産学会春季大会
  • Place of Presentation: 東京
  • Year and Date: 2013-02-06
• [Presentation] アサリに寄生するPerkinsus属原虫2種の国内分布 (2013)
  • Author(s): 梅田剛佑・良永知義
  • Organizer: 平成25年度日本魚病学会春季大会
  • Place of Presentation: 日本大学生物資源科学部湘南キャンパス(神奈川県）
• [Presentation] アサリに寄生する Perkinsus 属原虫の病害性の実験的な評価 (2013)
  • Author(s): 脇 司・良永知義
  • Organizer: 平成25年度日本水産学会春季大会
  • Place of Presentation: 東京海洋大学（品川キャンパス）
• [Presentation] 有明海定点における Perkinsus 属原虫のアサリの減耗への関与 (2013)
  • Author(s): 脇 司・高橋美希・悦喜達也・日浅大仁・梅田剛佑・高岸奈々絵・良永知義
  • Organizer: 平成25年度日本水産学会春季大会
  • Place of Presentation: 東京海洋大学（品川キャンパス）
• [Presentation] アサリのPerkinsus属原虫の分布に影響する環境要因について (2013)
  • Author(s): 梅田剛佑・高橋美希・脇 司・悦喜達也・良永知義
  • Organizer: 平成25年度日本水産学会春季大会
  • Place of Presentation: 東京海洋大学（品川キャンパス）
• [Presentation] Development of real-time PCR assay for discrimination and quantification of two Perkinsus spp. in Manila Clam Ruditapes philippinarum (2011)
  • Author(s): Umeda, K.・Yoshinaga, T
  • Organizer: 8th symposium of Diseases of Aqsia Aquaculture
  • Place of Presentation: Mangalore, India
  • Year and Date: 2011-11-23
• [Presentation] Development of a real-time PCR assay for discrimination and quantification of two Perkinsus spp.in the Manila Clam Ruditapes (2011)
  • Author(s): Umeda, K, Yoshianga, T
  • Organizer: 8th Symposium of Diseases on Asain Aquaculture
  • Place of Presentation: Mangalore,インド
  • Year and Date: 2011-11-23
• [Presentation] 野外調査アサリにおけるパーキンサス感染強度定量のためのRFTM法の標準化 (2011)
  • Author(s): 悦喜達也・良永知義
  • Organizer: 平成23年度日本魚病学会春季大会
  • Place of Presentation: 長崎
  • Year and Date: 2011-10-02
• [Presentation] 野外調査アサリ試料におけるパーキンサス感染強度定量のためのRFTM法の標準化 (2011)
  • Author(s): 悦喜達也・良永知義
  • Organizer: 平成23年度日本魚病学会秋季大会
  • Place of Presentation: 長崎大学
  • Year and Date: 2011-10-02
• [Presentation] アサリに寄生するPerkinsus属原虫2種のReal-timePCRによる識別・定量法 (2011)
  • Author(s): 梅田剛佑・高橋美希・良永知義・小川和夫
  • Organizer: 平成23年度日本魚病学会春季大会
  • Place of Presentation: 東京
  • Year and Date: 2011-03-26
• [Presentation] アサリに寄生するPerkinsus属2種の攻撃試験法の開発 (2011)
  • Author(s): 高橋美希・良永知義・小川和夫
  • Organizer: 平成23年度日本魚病学会春季大会
  • Year and Date: 2011-03-26
• [Presentation] アサリに寄生する Perkinsus 属原虫2種のReal-timePCRによる識別・定量法 (2011)
  • Author(s): 梅田剛佑・高橋美希・良永知義・小川和夫
  • Organizer: 平成23年度日本魚病学会春季大会
  • Place of Presentation: 東京
  • Year and Date: 2011-03-26