{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T17:40:26Z","timestamp":1790185226703,"version":"4.1.0"},"reference-count":16,"publisher":"CSIRO Publishing","issue":"11","license":[{"start":{"date-parts":[[2025,5,27]],"date-time":"2025-05-27T00:00:00Z","timestamp":1748304000000},"content-version":"vor","delay-in-days":2980,"URL":"https:\/\/doi.org\/10.1071\/journalslicense"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2017,10,3]]},"abstract":"<jats:p>The aim of the present study was to develop a protocol for the successful cryopreservation of Saltwater crocodile spermatozoa. Sperm cells were frozen above liquid nitrogen vapour in phosphate-buffered saline (PBS) containing either 0.3 M trehalose, 0.3 M raffinose or 0.3 M sucrose and compared with glycerol (0.3\u20132.7 M). Although the highest levels of mean post-thaw motility were observed following cryopreservation in 0.3 M trehalose (7.6%) and 0.3 M sucrose (7.3%), plasma membrane integrity (PI) was best following cryopreservation in 2.7 M glycerol (52.5%). A pilot study then assessed the cytotoxicity of glycerol and sucrose prior to cryopreservation and revealed no loss of survival when spermatozoa were diluted in 0.68 M glycerol or 0.2\u20130.3 M sucrose once cryoprotectants were washed out with PBS or Biggers, Whitten and Whittingham medium containing sperm capacitation agents (BWWCAP). A final study refined the combined use of permeating (0.68 or 1.35 M glycerol) and non-permeating (0.2 or 0.3 M sucrose) cryoprotectants. Spermatozoa were cryopreserved in liquid nitrogen vapour at rates of approximately -21\u00b0C min-1 (fast freeze) or -6.0\u00b0C min-1 (slow freeze). Post-thaw survival was highest with a combination of 0.2 M sucrose and 0.68 M glycerol and when these cryoprotectants were washed out with BWWCAP, regardless of whether spermatozoa were frozen using a fast (motility 14.2 \u00b1 4.7%; PI 20.7 \u00b1 2.0%) or slow (motility 12.0 \u00b1 2.7%; PI 22 \u00b1 4%) cryopreservation rate.<\/jats:p>","DOI":"10.1071\/rd16511","type":"journal-article","created":{"date-parts":[[2017,3,30]],"date-time":"2017-03-30T00:06:18Z","timestamp":1490832378000},"page":"2235-2244","source":"Crossref","is-referenced-by-count":24,"title":["Cryopreservation of saltwater crocodile (Crocodylus porosus) spermatozoa"],"prefix":"10.1071","volume":"29","author":[{"given":"S. D.","family":"Johnston","sequence":"first","affiliation":[{"name":"ASchool of Agriculture and Food Science, The University of Queensland, Gatton, Qld 4343, Australia."},{"name":"GCorresponding author. 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L.","family":"Anderson","sequence":"additional","affiliation":[{"name":"DSchool of Environmental and Life Sciences, The University of Newcastle, Callaghan, NSW 2308, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R.","family":"Hobbs","sequence":"additional","affiliation":[{"name":"ETaronga Conservation Society, Mosman, NSW 2088, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J.","family":"Gos\u00e1lvez","sequence":"additional","affiliation":[{"name":"FDepartment of Biology, Universidad Aut\u00f3noma de Madrid, Madrid, 20849, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C.","family":"L\u00f3pez-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"FDepartment of Biology, Universidad Aut\u00f3noma de Madrid, Madrid, 20849, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"T.","family":"Keeley","sequence":"additional","affiliation":[{"name":"ASchool of Agriculture and Food Science, The University of Queensland, Gatton, Qld 4343, Australia."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"67","published-online":{"date-parts":[[2017,3,30]]},"reference":[{"key":"2025102819315089500_R1"},{"key":"2025102819315089500_R2","first-page":"366","article-title":"Determination of the best practical method of thawing bovine semen.","volume":"29","author":"Barth","year":"1988","journal-title":"Can. Vet. J."},{"key":"2025102819315089500_R3"},{"key":"2025102819315089500_R4","first-page":"165","article-title":"Reptile and amphibian conservation through gene banking and other reproduction technologies.","volume":"18","author":"Browne","year":"2011","journal-title":"Russ. J. Herpetol."},{"key":"2025102819315089500_R5","doi-asserted-by":"publisher","first-page":"1116","DOI":"10.1071\/RD15466","article-title":"Cryopreservation and other assisted reproductive technologies for the conservation of threatened amphibians and reptiles: bringing the ARTs up to speed.","volume":"28","author":"Clulow","year":"2016","journal-title":"Reprod. Fertil. Dev."},{"key":"2025102819315089500_R6"},{"key":"2025102819315089500_R7"},{"key":"2025102819315089500_R8","unstructured":"Johnston, S. D., Lever, J., McLeod, R., Oishi, M., and Collins, S. (2014a). Development of breeding techniques in the crocodile industry. RIRDC Publication No. 13\/097, RIRDC Project No. PRJ006157. 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