{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T20:02:19Z","timestamp":1780344139883,"version":"3.54.1"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,27]],"date-time":"2021-12-27T00:00:00Z","timestamp":1640563200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Bacterial contamination of boar semen occurs with some frequency in artificial insemination centers and may have a negative effect on the quality of the semen as well as on the sows\u2019 reproductive capacity. Normally, the source of bacterial contamination in pig seminal doses is the own boar. However, distilled water or laboratory equipment used to elaborate the seminal doses can be an important source of bacterial contamination. This study focused on the identification of gram-negative bacteria in boar semen, and impact on the quality of ejaculates obtained from boar, as well as on the establishment of antimicrobial resistance patterns of isolated gram-negative bacteria. Semen samples were collected from 96 boars, ranging in age from 12\u201336 month, from three artificial insemination centers from the North-West of Romania. Bacterial species were identified by two methods: matrix-assisted laser desorption\/ionization time-of-flight (MALDI-TOF) mass spectrometry and API 20 E (BioMerieux, France). The main bacteria isolated from the doses diluted semen were gram-negative bacteria (47.91%), with a majority of the contaminant bacteria belonging to the family Enterobacteriaceae: Seratia marcescens 19.56%, Proteus mirabilis 15.21% and Escherichia coli 10.86% and to the family Pseudomonaceae: Ralstonia picketii 17.39%, Burkholderia cepacia 10.86%, Pseudomonas aeruginosa 8.69%, and Pseudomonas fluorescens 4.34%, respectively. More than half of these isolates (56.52%) were resistant to gentamycin and 58.69% were resistant to penicillin. These antibiotics are very frequently added in sperm diluent in the centers for the processing of sperm from boars in Romania. Regular monitoring for bacterial contamination is an important aspect of a control program.<\/jats:p>","DOI":"10.3390\/ani12010043","type":"journal-article","created":{"date-parts":[[2021,12,28]],"date-time":"2021-12-28T01:18:15Z","timestamp":1640654295000},"page":"43","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Boar Semen Contamination: Identification of Gram-Negative Bacteria and Antimicrobial Resistance Profile"],"prefix":"10.3390","volume":"12","author":[{"given":"Luminita","family":"Costinar","sequence":"first","affiliation":[{"name":"Infectious Diseases Department, Faculty of Veterinary Medicine, Banat\u2019s University of Agricultural Sciences and Veterinary Medicine \u201cKing Michael I of Romania\u201d from Timisoara, 119 Aradului Street Timisoara, Timis County, 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":"Infectious Diseases Department, Faculty of Veterinary Medicine, Banat\u2019s University of Agricultural Sciences and Veterinary Medicine \u201cKing Michael I of Romania\u201d from Timisoara, 119 Aradului Street Timisoara, Timis County, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Pitoiu","sequence":"additional","affiliation":[{"name":"Synevovet Laboratory, Industriilor Street, No. 25, Chiajna, Ilfov County, 077040 Chiajna, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ionica","family":"Iancu","sequence":"additional","affiliation":[{"name":"Infectious Diseases Department, Faculty of Veterinary Medicine, Banat\u2019s University of Agricultural Sciences and Veterinary Medicine \u201cKing Michael I of Romania\u201d from Timisoara, 119 Aradului Street Timisoara, Timis County, 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":"Infectious Diseases Department, Faculty of Veterinary Medicine, Banat\u2019s University of Agricultural Sciences and Veterinary Medicine \u201cKing Michael I of Romania\u201d from Timisoara, 119 Aradului Street Timisoara, Timis County, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anca","family":"Hulea","sequence":"additional","affiliation":[{"name":"Infectious Diseases Department, Faculty of Veterinary Medicine, Banat\u2019s University of Agricultural Sciences and Veterinary Medicine \u201cKing Michael I of Romania\u201d from Timisoara, 119 Aradului Street Timisoara, Timis County, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1013-0437","authenticated-orcid":false,"given":"Corina","family":"Pascu","sequence":"additional","affiliation":[{"name":"Infectious Diseases Department, Faculty of Veterinary Medicine, Banat\u2019s University of Agricultural Sciences and Veterinary Medicine \u201cKing Michael I of Romania\u201d from Timisoara, 119 Aradului Street Timisoara, Timis County, 300645 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"565","DOI":"10.1016\/j.theriogenology.2013.05.022","article-title":"Adverse effects of members of the Enterobacteriaceae family on boar sperm quality","volume":"80","author":"Ausejo","year":"2013","journal-title":"Theriogenology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1167","DOI":"10.1016\/S0093-691X(00)00261-2","article-title":"Field investigations of bacterial contaminants and their effects on extended porcine semen","volume":"53","author":"Althouse","year":"2000","journal-title":"Theriogenology"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"573","DOI":"10.1016\/j.theriogenology.2004.09.031","article-title":"Bacteriospermia in extended porcine semen","volume":"63","author":"Althouse","year":"2005","journal-title":"Theriogenology"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1016\/j.theriogenology.2015.09.049","article-title":"The impact of bacteriospermia on boar sperm storage and reproductive performance","volume":"85","author":"Kuster","year":"2016","journal-title":"Theriogenology"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"374","DOI":"10.1111\/j.1439-0531.2008.01187.x","article-title":"Sanitary procedures for the production of extended semen","volume":"43","author":"Althouse","year":"2008","journal-title":"Reprod. 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