Development of control strategies against avian colibacillosis using bacteriophages

• Project/Area Number: 16K08050
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Veterinary medical science
• Research Institution: Tottori University
• Principal Investigator: Murase Toshiyuki 鳥取大学, 農学部, 教授 (20229983)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2018: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2017: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2016: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 大腸菌 / 鶏 / バクテリオファージ / 鶏大腸菌症 / 大腸菌症 / 発育鶏卵 / 鶏舎 / 環境 / 微生物 / 細菌 / ウイルス / 感染症

Outline of Final Research Achievements

Bacteriophages (phages) that lyse avian pathogenic Escherichia coli (APEC) can be used as a measure for controlling APEC as an alternative to antimicrobials. Results obtained in the present study are as follows: the temperature is important for isolation of phages from environmental samples; combination of multiple phage samples resulted in lysing APEC isolates with high heterogeneity; application of APEC-lytic phages reduced viable cell counts of APEC isolates in the condition imitating chicken farms; and the therapeutic effect of APEC-lytic phages on colibacillosis was found in an infectious model of this disease.

Academic Significance and Societal Importance of the Research Achievements

養鶏産業における課題のひとつである鶏大腸菌症の原因菌（APEC）は性状が多様であるほか、抗菌薬が効かない薬剤耐性菌が多いことが知られている。本研究において、環境中からファージを効率的に分離する条件を見出したため、多様なAPECを溶菌するファージを分離し、それらを組み合わせて利用するすることが可能となった。また、模擬的な鶏舎環境や感染モデルにおいてAPECを制御しうる成績が得られたことから、フィールドにおける応用に向けた検討が可能となった。

Research Products

• [Journal Article] Virulence of Escherichia coli Isolates Obtained from Layer Chickens with Colibacillosis Associated with Pericarditis, Perihepatitis, and Salpingitis in Experimentally Infected Chicks and Embryonated Eggs (2018)
  • Author(s): Ozaki H.、Yonehara K.、Murase T.
  • Journal Title: Avian Diseases Volume: 62 Issue: 2 Pages: 233-236
  • DOI: 10.1637/11685-060717-resnote.1
  • Peer Reviewed
• [Journal Article] Virulence of Escherichia coli isolates obtained from layer chickens with colibacillosis associated with pericarditis, perihepatitis, and salpingitis in experimentally infected chicks and embryonated eggs (2018)
  • Author(s): Ozaki H.、Yonehara K.、Murase T.
  • Journal Title: Avian Diseases Volume: 62
  • Peer Reviewed
• [Journal Article] Characteristics of Escherichia coli isolated from broiler chickens with colibacillosis in commercial farms from a common hatchery (2017)
  • Author(s): Ozaki H.、Matsuoka Y.、Nakagawa E.、Murase T.
  • Journal Title: Poultry Science Volume: 96 Issue: 10 Pages: 3717-3724
  • DOI: 10.3382/ps/pex167
  • Peer Reviewed
• [Presentation] 発育鶏卵に接種したAvian Pathogenic Escherichia coli（APEC）のバクテリオファージによる病原性抑制効果 (2018)
  • Author(s): 尾崎 弘一、関原 雄大、村瀬 敏之
  • Organizer: 第161回 日本獣医学会学術集会
• [Presentation] Avian Pathogenic Escherichia coli（APEC）を溶菌するバクテリオファージの分離条件の検討 (2017)
  • Author(s): 尾崎 弘一、中村 あさひ、村瀬 敏之
  • Organizer: 第160回 日本獣医学会学術集会
• [Presentation] 鶏飼養農場からの大腸菌バクテリオファージの分離と性状解析 (2016)
  • Author(s): 尾崎 弘一、関原 雄大、村瀬 敏之
  • Organizer: 第159回日本獣医学会学術集会
  • Place of Presentation: 藤沢市
  • Year and Date: 2016-09-08