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Working towards this goal, our research has focused on the saltwater crocodile Crocodylus porosus as a tractable model for understanding crocodilian sperm physiology. In extending our systematic characterisation of saltwater crocodile spermatozoa, in this study we examined the development of motility during sperm transport through the excurrent duct system of the male crocodile. The results show that approximately 20% of crocodile testicular spermatozoa are immediately motile but experience a gradient of increasing motility (percentage motile and rate of movement) as they transit the male reproductive tract (epididymis). Moreover, we confirmed that, as in ejaculated crocodile spermatozoa, increased intracellular cAMP levels promoted a significant and sustained enhancement of sperm motility regardless of whether the cells were isolated from the testis or epididymis. Along with the development of artificial reproductive technologies, this research paves the way for the opportunistic recovery, storage and potential utilisation of post-mortem spermatozoa from genetically valuable animals.<\/jats:p>","DOI":"10.1071\/rd20204","type":"journal-article","created":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T18:12:55Z","timestamp":1614276775000},"page":"530-539","source":"Crossref","is-referenced-by-count":9,"title":["Post-testicular sperm maturation in the saltwater crocodile Crocodylus porosus: assessing the temporal acquisition of sperm motility"],"prefix":"10.1071","volume":"33","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2745-8188","authenticated-orcid":true,"given":"Brett","family":"Nixon","sequence":"first","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."},{"name":"FCorresponding author. Email: brett.nixon@newcastle.edu.au"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amanda L.","family":"Anderson","sequence":"additional","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth G.","family":"Bromfield","sequence":"additional","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacinta H.","family":"Martin","sequence":"additional","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shenae L.","family":"Cafe","sequence":"additional","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David A.","family":"Skerrett-Byrne","sequence":"additional","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew D.","family":"Dun","sequence":"additional","affiliation":[{"name":"CCancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"DPriority Research Centre for Cancer Research Innovation and Translation, Hunter Medical Research Institute, Lambton, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew L.","family":"Eamens","sequence":"additional","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geoffry N.","family":"De Iuliis","sequence":"additional","affiliation":[{"name":"APriority Research Centre for Reproductive Science, School of Environmental and Life Sciences, Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia."},{"name":"BHunter Medical Research Institute, Pregnancy and Reproduction Program, New Lambton Heights, NSW 2305, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0290-5458","authenticated-orcid":true,"given":"Stephen D.","family":"Johnston","sequence":"additional","affiliation":[{"name":"ESchool of Agriculture and Food Sciences, The University of Queensland, Gatton, Qld 4343, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"67","published-online":{"date-parts":[[2021,2,26]]},"reference":[{"key":"2025102820133782500_R1","doi-asserted-by":"publisher","first-page":"785","DOI":"10.1093\/MOLEHR\/GAT067","article-title":"Sperm capacitation: a distant landscape glimpsed but unexplored.","volume":"19","author":"Aitken","year":"2013","journal-title":"Mol. 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