{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T15:33:08Z","timestamp":1779377588196,"version":"3.53.1"},"reference-count":41,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,3,19]],"date-time":"2023-03-19T00:00:00Z","timestamp":1679184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Association for Bioeconomy Research (FBF e.V.)","award":["CoolSperm 281DT01B21"],"award-info":[{"award-number":["CoolSperm 281DT01B21"]}]},{"name":"erman Federal Ministry of Food and Agriculture","award":["CoolSperm 281DT01B21"],"award-info":[{"award-number":["CoolSperm 281DT01B21"]}]},{"name":"Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)\u2014491094227 \u201cOpen Access Publication Funding\u201d and the University of Veterinary Medicine Hannover, Foundation","award":["CoolSperm 281DT01B21"],"award-info":[{"award-number":["CoolSperm 281DT01B21"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The aim of this study was first to examine the prevalence of bacteria-associated loss of sperm quality in samples from insemination centers during a seven-year semen monitoring program and, second, to investigate the growth dynamic of four different multidrug-resistant bacterial species and their impact on sperm quality during semen storage. A reduced sperm quality associated with bacterial contamination was found in 0.5% of 3219 of the samples from insemination centers. In samples spiked with Serratia marcescens and Klebsiella oxytoca, bacterial growth by six log levels was seen during storage at 17 \u00b0C, causing loss of sperm motility, membrane integrity, membrane fluidity, and mitochondrial membrane potential at &gt;107 CFU\/mL (p &lt; 0.05). Storage at 5 \u00b0C in the Androstar Premium extender efficiently inhibited their growth. Achromobacter xylosoxidans and Burkholderia cepacia showed limited growth up to two log levels at 17 \u00b0C and did not impair sperm quality. In conclusion, spermatozoa tolerate moderate loads of multidrug-resistant bacteria, and hypothermic, antibiotic-free semen storage effectively limits bacterial growth. The constant use of antibiotics in semen extenders should be reconsidered.<\/jats:p>","DOI":"10.3390\/microorganisms11030788","type":"journal-article","created":{"date-parts":[[2023,3,20]],"date-time":"2023-03-20T06:48:35Z","timestamp":1679294915000},"page":"788","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Growth Dynamic and Threshold Values for Spermicidal Effects of Multidrug-Resistant Bacteria in Extended Boar Semen"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5305-2355","authenticated-orcid":false,"given":"Anne-Marie","family":"Luther","sequence":"first","affiliation":[{"name":"Unit for Reproductive Medicine, Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, B\u00fcnteweg 15, D-30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Beckermann","sequence":"additional","affiliation":[{"name":"Unit for Reproductive Medicine, Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, B\u00fcnteweg 15, D-30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thu Quynh","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Unit for Reproductive Medicine, Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, B\u00fcnteweg 15, D-30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jutta","family":"Verspohl","sequence":"additional","affiliation":[{"name":"Institute for Microbiology, University of Veterinary Medicine Hannover, Foundation, Bischofsholer Damm 15, D-30173 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6616-2035","authenticated-orcid":false,"given":"Dagmar","family":"Waberski","sequence":"additional","affiliation":[{"name":"Unit for Reproductive Medicine, Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, B\u00fcnteweg 15, D-30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1016\/j.theriogenology.2019.05.030","article-title":"Application of Preserved Boar Semen for Artificial Insemination: Past, Present and Future Challenges","volume":"137","author":"Waberski","year":"2019","journal-title":"Theriogenology"},{"key":"ref_2","unstructured":"AGISAR, and WHO (2022, September 05). 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