{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T05:20:13Z","timestamp":1780464013857,"version":"3.54.1"},"reference-count":31,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,3,29]],"date-time":"2022-03-29T00:00:00Z","timestamp":1648512000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deutsche Forschungsgemeinschaft","award":["491292795"],"award-info":[{"award-number":["491292795"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Giraffe numbers have plummeted over the last 30 years by 30\u201340%. Thus, their conservation status has been raised from least concern to vulnerable. Efforts to manage in situ and ex situ populations are increasing. Assisted reproduction techniques (ART) such as sperm cryopreservation could help preserve the genetic diversity of giraffe subspecies and, when used for artificial inseminations, enhance genetic exchange between isolated populations. However, to date, the post-thaw motility of recovered sperm has been low and inconsistent. In this study, epididymal sperm collected from the testes of giraffes (n = 7) was frozen in three different extenders, namely, BotuCrio, Steridyl, and test egg yolk (TEY), each supplemented with one of two different cryoprotectants (5% glycerol or a mix of 1% glycerol and 4% methylformamide) and frozen over liquid nitrogen vapor. Across all three extenders, sperm showed significantly better post-thaw results when frozen with a mix of glycerol and methylformamide compared with glycerol alone. Sperm frozen with TEY and a mix of glycerol and methylformamide achieved superior post-thaw total and progressive sperm motility of 57 \u00b1 3% and 45 \u00b1 3%, respectively. These results show the benefit of using alternative cryoprotectants for freezing giraffe spermatozoa and could aid in the application of ARTs for giraffe subspecies or the closely related endangered Okapi.<\/jats:p>","DOI":"10.3390\/ani12070857","type":"journal-article","created":{"date-parts":[[2022,3,29]],"date-time":"2022-03-29T21:40:14Z","timestamp":1648590014000},"page":"857","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Cryopreservation of Giraffe Epidydimal Spermatozoa Using Different Extenders and Cryoprotectants"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2487-9171","authenticated-orcid":false,"given":"Robert","family":"Hermes","sequence":"first","affiliation":[{"name":"Department Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, D-10315 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexis","family":"Lecu","sequence":"additional","affiliation":[{"name":"Parc Zoologique de Paris, MNHN, F-75012 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7659-9334","authenticated-orcid":false,"given":"Romain","family":"Potier","sequence":"additional","affiliation":[{"name":"Faune Vet, F-44200 Nantes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5353-7499","authenticated-orcid":false,"given":"Frank","family":"Goeritz","sequence":"additional","affiliation":[{"name":"Department Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, D-10315 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4137-2818","authenticated-orcid":false,"given":"Jessica P.","family":"Rickard","sequence":"additional","affiliation":[{"name":"School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, NSW 2006, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Bohner","sequence":"additional","affiliation":[{"name":"Serengeti-Park Hodenhagen, D-29693 Hodenhagen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rudy","family":"Wedlarski","sequence":"additional","affiliation":[{"name":"Bioparc de Dou\u00e9-la-Fontaine, F-49700 Dou\u00e9-la-Fontaine, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiri","family":"Hruby","sequence":"additional","affiliation":[{"name":"ZOO Dv\u016fr Kr\u00e1lov\u00e9, CZ-544 01 Dv\u016fr Kr\u00e1lov\u00e9 nad Labem, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8685-4733","authenticated-orcid":false,"given":"Thomas B.","family":"Hildebrandt","sequence":"additional","affiliation":[{"name":"Department Reproduction Management, Leibniz Institute for Zoo and Wildlife Research, D-10315 Berlin, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,29]]},"reference":[{"key":"ref_1","unstructured":"Muller, Z., Bercovitch, F., Brand, R., Brown, D., Brown, M., Bolger, D., Carter, K., Deacon, F., Doherty, J.B., and Fennessy, J. 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