{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T16:52:57Z","timestamp":1791564777850,"version":"4.3.4"},"reference-count":42,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,6,26]],"date-time":"2025-06-26T00:00:00Z","timestamp":1750896000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Life Sciences \u201cKing Mihai I\u201d from Timi\u0219oara, Romania"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Bovine uterine infections remain a widespread challenge in dairy production systems, contributing to reduced fertility and overall herd performance. Background\/Objectives: Postpartum uterine infections significantly affect dairy cattle fertility and productivity. This study aimed to identify aerobic bacterial pathogens associated with clinical endometritis in Romanian dairy cows and evaluate their antimicrobial resistance profiles. Methods: Uterine swab samples (n = 348) were collected from clinically affected cows across multiple farms. Bacteria were isolated and identified using conventional culture methods and MALDI-TOF MS. Antimicrobial susceptibility testing was performed using the VITEK\u00ae 2 system with GN 96 and GP 79 cards. Statistical analysis was conducted using the chi-square (\u03c72) test. Results: A total of 387 bacterial isolates were recovered, with over half of the samples showing mixed bacterial contamination. Escherichia coli was the most frequently identified pathogen (44.9%), followed by Staphylococcus spp. (17.3%) and Klebsiella spp. (14.5%). Gram-negative isolates showed high resistance to tetracycline and ampicillin, while retaining susceptibility to imipenem and polymyxin B. Among Gram-positive isolates, Streptococcus spp. were highly susceptible to \u03b2-lactams, while Staphylococcus spp. showed moderate resistance to penicillin and macrolides. Conclusions: This study highlights the prevalence of key aerobic pathogens and their resistance profiles in Romanian dairy herds. These findings support the need for targeted diagnostics and rational antimicrobial use to improve uterine health and therapeutic outcomes in dairy cattle.<\/jats:p>","DOI":"10.3390\/antibiotics14070650","type":"journal-article","created":{"date-parts":[[2025,6,27]],"date-time":"2025-06-27T03:33:25Z","timestamp":1750995205000},"page":"650","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Aerobic Uterine Pathogens in Dairy Cattle: Surveillance and Antimicrobial Resistance Profiles in Postpartum Endometritis"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8913-4942","authenticated-orcid":false,"given":"Ionica","family":"Iancu","sequence":"first","affiliation":[{"name":"Department of Infectious Diseases and Preventive Medicine, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1684-7324","authenticated-orcid":false,"given":"Sebastian Alexandru","family":"Popa","sequence":"additional","affiliation":[{"name":"Department of Animal Production and Veterinary Public Health, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5859-5057","authenticated-orcid":false,"given":"Janos","family":"Degi","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Preventive Medicine, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2531-6469","authenticated-orcid":false,"given":"Alexandru","family":"Gligor","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Preventive Medicine, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-6286-5523","authenticated-orcid":false,"given":"Ionela","family":"Popa","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Preventive Medicine, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-2799-6191","authenticated-orcid":false,"given":"Vlad","family":"Iorgoni","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Preventive Medicine, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paula","family":"Nistor","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Preventive Medicine, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6057-882X","authenticated-orcid":false,"given":"K\u00e1lm\u00e1n","family":"Imre","sequence":"additional","affiliation":[{"name":"Department of Animal Production and Veterinary Public Health, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4823-5741","authenticated-orcid":false,"given":"Ileana","family":"Nichita","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7118-6488","authenticated-orcid":false,"given":"Viorel","family":"Herman","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Preventive Medicine, Faculty of Veterinary Medicine, University of Life Science \u201cKing Mihai I\u201d, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2223","DOI":"10.3168\/jds.S0022-0302(02)74302-6","article-title":"Defining and diagnosing postpartum clinical endometritis and its impact on reproductive performance in dairy cows","volume":"85","author":"LeBlanc","year":"2002","journal-title":"J. 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