Development of a new therapeutic method using phage for endometritis in cows

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K08055
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Veterinary medical science
• Research Institution: Kagoshima University
• Principal Investigator: Ando Takaaki 鹿児島大学, 農水産獣医学域獣医学系, 准教授 (40406898)
• Co-Investigator(Kenkyū-buntansha): 樋口 豪紀 酪農学園大学, 獣医学群, 教授 (00305905) ; 岩野 英知 酪農学園大学, 獣医学群, 教授 (60382488) ; 窪田 力 鹿児島大学, 農水産獣医学域獣医学系, 教授 (80420652)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 牛 / 繁殖 / 子宮 / 細菌 / ファージ

Outline of Final Research Achievements

We collected perfusate from the uterus, isolated the bacteria in 50 Japanese black cows and 50 Holstein cows two weeks after calving. In Japanese Black cows, bacteria were isolated from 32 (64%), of which 20 (63%) were Escherichia coli (E. coli). On the other hand, in the Holstein cows, bacteria were isolated from 28 (56%), of which 16 (57%) were E. coli. Phages were isolated from environmental water, and Escherichia coli growth inhibition test using the turbidity method was carried out on phages. When the culture was performed only with E. coli, the absorbance increased 2 hours after the start of the culture, whereas when the same number of phages were mixed with the number of bacteria and the culture was performed, the increase of absorbance until 7 hours after the start of the culture was not seen. From these results, it could be used as a new therapeutic method for bacterial intrauterine infection in postpartum cows.

Free Research Field

臨床獣医学

Academic Significance and Societal Importance of the Research Achievements

本研究は、新規の治療法であるファージを用いた子宮内膜炎の治療法の開発と臨床応用に関しての基礎的研究を行った。E.coli以外の菌種に対しても有効なファージを複数合わせたカクテル化が成功すれば、臨床現場では菌種を特定することなく使用することができ、広く汎用性を持たせることが可能となる。さらに、この治療法を確立することで抗生剤への耐性化が進む細菌の感染症に対して、安全な治療法を確立することが可能となる。さらに、この治療法を確立することで抗生剤の耐性化の抑制と使用量削減により食の安全性に寄与し、空胎期間の短縮や授精回数の減少により牛の生産性を向上させることが可能となる。