{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T10:31:09Z","timestamp":1784197869133,"version":"3.55.0"},"reference-count":27,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,4,16]],"date-time":"2020-04-16T00:00:00Z","timestamp":1586995200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Animal and Plant Quarantine Agency, Ministry of Agriculture, Food, and Rural Affairs, Republic of Korea","award":["Z-1543081-2017-18-01"],"award-info":[{"award-number":["Z-1543081-2017-18-01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>The increasing prevalence of antimicrobial resistance and the laborious development of novel antimicrobial agents have limited the options for effective antimicrobial therapy. The combination of previously used antimicrobial agents represents an alternative therapy for multidrug-resistant (MDR) pathogens. The objective of this study was to investigate the synergistic effect of a florfenicol (FFL)-based combination with other antimicrobial agents against MDR Escherichia coli isolates from livestock using checkerboard assays and murine infection models. The FFL\/amikacin (AMK) and FFL\/gentamicin (GEN) combinations showed synergy against 10\/11 and 6\/11 MDR E. coli isolates in vitro, respectively. The combination of FFL with aminoglycosides (AMK or GEN) exhibited a better synergistic effect against MDR E. coli isolates than the cephalothin (CEF)\/GEN or FFL\/CEF combinations. The combination of FFL with AMK or GEN could reduce the emergence of resistant mutants in vitro. The FFL\/AMK combination showed a higher survival rate of mice infected with MDR E. coli isolates than FFL or AMK alone. In summary, the combination of FFL with aminoglycosides (AMK or GEN) is highly effective against MDR E. coli isolates both in vitro and in vivo. Our findings may contribute to the discovery of an effective combination regimen against MDR E. coli infections in veterinary medicine.<\/jats:p>","DOI":"10.3390\/antibiotics9040185","type":"journal-article","created":{"date-parts":[[2020,4,16]],"date-time":"2020-04-16T13:01:39Z","timestamp":1587042099000},"page":"185","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Synergy between Florfenicol and Aminoglycosides against Multidrug-Resistant Escherichia coli Isolates from Livestock"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3322-7984","authenticated-orcid":false,"given":"Shukho","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Microbiology, School of Medicine, Kyungpook National University, Daegu 41944, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jung Hwa","family":"Woo","sequence":"additional","affiliation":[{"name":"Department of Microbiology, School of Medicine, Kyungpook National University, Daegu 41944, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"So Hyun","family":"Jun","sequence":"additional","affiliation":[{"name":"Department of Microbiology, School of Medicine, Kyungpook National University, Daegu 41944, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1244-201X","authenticated-orcid":false,"given":"Dong Chan","family":"Moon","sequence":"additional","affiliation":[{"name":"Bacterial Disease Division, Animal and Plant Quarantine Agency, Gimcheon-si, Gyeongsangbuk-do 39660, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7549-9411","authenticated-orcid":false,"given":"Suk-Kyung","family":"Lim","sequence":"additional","affiliation":[{"name":"Bacterial Disease Division, Animal and Plant Quarantine Agency, Gimcheon-si, Gyeongsangbuk-do 39660, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Je Chul","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Microbiology, School of Medicine, Kyungpook National University, Daegu 41944, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1128\/microbiolspec.ARBA-0026-2017","article-title":"Antimicrobial Resistance in Escherichia coli","volume":"6","author":"Poirel","year":"2018","journal-title":"Microbiol. 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