Clarifying the farm environment (compost and livestock wastewater) as a hotspot for antimicrobial resistance and proposing a control method

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H04285
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 63040:Environmental impact assessment-related
• Research Institution: Rakuno Gakuen University
• Principal Investigator: Usui Masaru 酪農学園大学, 獣医学群, 准教授 (60639540)
• Co-Investigator(Kenkyū-buntansha): 東 剛志 大阪医科薬科大学, 薬学部, 助教 (10634222) ; 高田 秀重 東京農工大学, (連合)農学研究科(研究院), 教授 (70187970)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 薬剤耐性 / 堆肥 / 畜産排水

Outline of Final Research Achievements

The emergence and spread of antimicrobial-resistant bacteria is an international problem. There is concern about the risk of AMR emerging in livestock and spreading to humans via manure and livestock wastewater. Therefore, we investigated the actual situation of AMR in farm environments by quantifying the amount of antimicrobial-resistant bacteria, resistant genes, and residual antimicrobials in compost and livestock wastewater, and developed a method to control AMR. As a result, it was found that the amount of antimicrobial resistant bacteria, resistant genes, and residual antimicrobials was higher in farms with high antimicrobial use. The study also elucidated that anaerobic digestion treatment and the use of additives are effective in reducing the risk of AMR in compost.

Free Research Field

獣医学、細菌学

Academic Significance and Societal Importance of the Research Achievements

抗菌薬の使用量の多い農場での堆肥中に薬剤耐性菌、耐性遺伝子、残留抗菌薬量が多いことを解明した。農場での適切な抗菌薬の使用を促したり、適切な家畜由来排泄物の処理を行う際の根拠を示した意義は大きい。
また、バイオガスプラント処理や添加剤の利用など、現状の問題点を解決する具体的な方法を示した意義も大きく、今後、野外農場での検証など、社会実装に向けた研究を推進していくことが期待される。