{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T04:10:21Z","timestamp":1785816621802,"version":"3.56.0"},"reference-count":22,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2024,1,24]],"date-time":"2024-01-24T00:00:00Z","timestamp":1706054400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>The rising prevalence of antimicrobial resistance (AMR) of bacteria is a global health problem at the human, animal, and environmental interfaces, which necessitates the \u201cOne Health\u201d approach. AMR of bacteria in animal feed are a potential cause of the prevalence in livestock; however, the role remains unclear. To date, there is limited research on AMR of bacteria in animal feed in Japan. In this study, a total of 57 complete feed samples and 275 feed ingredient samples were collected between 2018 and 2020. <jats:italic>Enterococcus<\/jats:italic> spp. were present in 82.5% of complete feed (47\/57 samples), 76.5% of soybean meal (62\/81), 49.6% of fish meal (55\/111), 33.3% of poultry meal (22\/66), and 47.1% of meat and bone meal (8\/17) samples. Of 295 isolates, <jats:italic>E. faecium<\/jats:italic> (33.2% of total isolates) was the dominant <jats:italic>Enterococcus<\/jats:italic> spp., followed by <jats:italic>E. faecalis<\/jats:italic> (14.2%), <jats:italic>E. hirae<\/jats:italic> (6.4%), <jats:italic>E. durans<\/jats:italic> (2.7%), <jats:italic>E. casseliflavus<\/jats:italic> (2.4%), and <jats:italic>E. gallinarum<\/jats:italic> (1.0%). Of 134 isolates which were tested for antimicrobial susceptibility, resistance to kanamycin was the highest (26.1%), followed by erythromycin (24.6%), tetracycline (6.0%), lincomycin (2.2%), tylosin (1.5%), gentamicin (0.8%), and ciprofloxacin (0.8%). All <jats:italic>Enterococcus<\/jats:italic> spp. exhibited susceptibility to ampicillin, vancomycin, and chloramphenicol. Of 33 erythromycin-resistant isolates, only two showed a high minimum inhibitory concentration value (&amp;gt;128\u2009\u03bcg\/mL) and possessed <jats:italic>ermB<\/jats:italic>. These results revealed that overall resistance to antimicrobials is relatively low; however, animal feed is a source of <jats:italic>Enterococcus<\/jats:italic> spp. It is essential to elucidate the causative factors related to the prevalence of AMR in animal feed.<\/jats:p>","DOI":"10.3389\/fvets.2023.1328552","type":"journal-article","created":{"date-parts":[[2024,1,24]],"date-time":"2024-01-24T04:22:18Z","timestamp":1706070138000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":11,"title":["Prevalence and antimicrobial resistance of Enterococcus spp. isolated from animal feed in Japan"],"prefix":"10.3389","volume":"10","author":[{"given":"Yohei","family":"Yamagami","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miyuki","family":"Asao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akiko","family":"Takahashi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshiyasu","family":"Hashimoto","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Noriko","family":"Okuyama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eiko","family":"Arai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wakana","family":"Arihara","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryota","family":"Masui","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoko","family":"Shimazaki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2024,1,24]]},"reference":[{"key":"ref1","unstructured":"2014"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"11993","DOI":"10.1021\/acs.est.5b02566","article-title":"Role of the environment in the transmission of antimicrobial resistance to humans: a review","volume":"49","author":"Huijbers","year":"2015","journal-title":"Environ Sci Technol"},{"key":"ref3","volume-title":"OIE standards, guidelines, and resolutions on antimicrobial resistance and the use of antimicrobial agents","year":"2020"},{"key":"ref4","volume-title":"Guidelines on integrated monitoring and surveillance of foodborne antimicrobial resistance. 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