{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T19:57:26Z","timestamp":1787169446496,"version":"build-2736575974"},"reference-count":37,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T00:00:00Z","timestamp":1630368000000},"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>Retained cytoplasmic droplets (CD) are the most frequent sperm abnormality in boar semen. A high incidence of CD is associated with subfertility, but the underlaying reasons are not well understood. The storage of extended semen might augment the adverse effects of CD on essential steps towards fertilization, such as capacitation. The aim of this study was to examine whether the enhanced presence of CD in boar semen influences sperm\u2019s response to the capacitation stimulus bicarbonate during long-term semen storage. Extended semen samples (n = 78) from 13 artificial insemination centers were analyzed using a flow cytometric calcium influx assay. Samples with &gt;15% of CD showed a reduced specific response to bicarbonate and a higher non-specific destabilization after storage for 96 h and subsequent incubation at 38 \u00b0C in three variants of Tyrode\u2019s medium (p &lt; 0.05). The size of the bicarbonate-responsive sperm population was inversely correlated with the presence of CD-bearing sperm (r = \u22120.61, p &lt; 0.01). Samples with \u226415% and samples with &gt;15% of CD did not differ in motility or viability and acrosome integrity during semen storage. In conclusion, incomplete epididymal sperm maturation impairs the in vitro capacitation ability and promotes sperm destabilization in stored boar semen.<\/jats:p>","DOI":"10.3390\/ani11092570","type":"journal-article","created":{"date-parts":[[2021,8,31]],"date-time":"2021-08-31T21:59:45Z","timestamp":1630447185000},"page":"2570","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["A High Incidence of Sperm with Cytoplasmic Droplets Affects the Response to Bicarbonate in Preserved Boar Semen"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4064-7792","authenticated-orcid":false,"given":"Heiko","family":"Henning","sequence":"first","affiliation":[{"name":"Unit for Reproductive Medicine, Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany"},{"name":"Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, 31535 Neustadt am R\u00fcbenberge, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5305-2355","authenticated-orcid":false,"given":"Anne-Marie","family":"Luther","sequence":"additional","affiliation":[{"name":"Unit for Reproductive Medicine, Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dagmar","family":"Waberski","sequence":"additional","affiliation":[{"name":"Unit for Reproductive Medicine, Clinic for Pigs and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1530\/rep.1.00814","article-title":"Binding of boar spermatozoa to oviductal epithelium in vitro in relation to sperm morphology and storage time","volume":"131","author":"Waberski","year":"2006","journal-title":"Reproduction"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"704","DOI":"10.1016\/j.theriogenology.2006.08.019","article-title":"Arachidonate 15-lipoxygenase and ubiquitin as fertility markers in boars","volume":"67","author":"Lovercamp","year":"2007","journal-title":"Theriogenology"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"139","DOI":"10.17151\/bccm.2015.19.2.8","article-title":"Dynamics of Sus scrofa semen quality in the western-central region of Colombia","volume":"19","author":"Mesa","year":"2015","journal-title":"Bolet\u00edn Cient\u00edfico Centro de Museos Museo de Historia Natural"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/0378-4320(94)90061-2","article-title":"Fertility of long-term-stored boar semen: Influence of extender (Androhep and Kiev), storage time and plasma droplets in the semen","volume":"36","author":"Waberski","year":"1994","journal-title":"Anim. 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