{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T04:00:06Z","timestamp":1790654406640,"version":"4.1.0"},"reference-count":22,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,11,8]],"date-time":"2022-11-08T00:00:00Z","timestamp":1667865600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Mahasarakham University (PM)"},{"name":"Elsa Paulssons Minnesfond (EW)"},{"name":"Agria SVT (JMM)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Antibiotics are added to semen extenders in insemination doses but their effect on the vaginal microbiota of the inseminated female is unknown. The objectives of this study were to define the equine vaginal microbiota and its antimicrobial resistance, and to determine whether it changes after exposure to antibiotics in semen extenders. Vaginal swabs were taken prior to sham-insemination (day 0), and again on days 3, 7, and 14 after insemination. Isolated bacteria were identified by MALDI-TOF and tested for antimicrobial susceptibility by microdilution. The bacteria isolated from the vagina differed according to reproductive status (brood mare or maiden mare), location (north or middle of Sweden), and the stage of the estrous cycle. Five bacterial species were frequently isolated from mares in both locations: Escherichia coli, Staphylococcus capitis, Streptococcus equisimilis, Streptococcus thoraltensis, and Streptococcus zooepidemicus. Overall, vaginal bacteria isolated from inseminated mares showed higher antibiotic resistance than from non-inseminated mares, suggesting a possible link between exposure to antibiotics in the semen extender and the appearance of antimicrobial resistance. The whole-genome sequencing of E. coli isolates from inseminated mares revealed some genes which are known to confer antimicrobial resistance; however, some instances of resistance in these isolates were not characteristic of induced AMR.<\/jats:p>","DOI":"10.3390\/microorganisms10112204","type":"journal-article","created":{"date-parts":[[2022,11,8]],"date-time":"2022-11-08T12:45:47Z","timestamp":1667911547000},"page":"2204","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Vaginal Bacteria in Mares and the Occurrence of Antimicrobial Resistance"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5508-4921","authenticated-orcid":false,"given":"Pongpreecha","family":"Malaluang","sequence":"first","affiliation":[{"name":"Department of Clinical Sciences, Swedish University of Agricultural Sciences (SLU), 75007 Uppsala, Sweden"},{"name":"Faculty of Veterinary Sciences, Mahasarakham University, Maha Sarakham 40000, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elin","family":"Wil\u00e9n","sequence":"additional","affiliation":[{"name":"Evidensia Horse Clinic, 96174 Boden, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4080-5183","authenticated-orcid":false,"given":"Sara","family":"Frosth","sequence":"additional","affiliation":[{"name":"Biomedical Science and Veterinary Public Health, Swedish University of Agricultural Sciences (SLU), 75007 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1175-0398","authenticated-orcid":false,"given":"Johanna","family":"Lindahl","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, Swedish University of Agricultural Sciences (SLU), 75007 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3764-2341","authenticated-orcid":false,"given":"Ingrid","family":"Hansson","sequence":"additional","affiliation":[{"name":"Biomedical Science and Veterinary Public Health, Swedish University of Agricultural Sciences (SLU), 75007 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5245-7331","authenticated-orcid":false,"given":"Jane M.","family":"Morrell","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, Swedish University of Agricultural Sciences (SLU), 75007 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3141","DOI":"10.3390\/ijerph7083141","article-title":"The Global Challenge of Antimicrobial Resistance: Insights from Economic Analysis","volume":"7","author":"Eggleston","year":"2010","journal-title":"Int. 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