{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,29]],"date-time":"2025-10-29T06:51:22Z","timestamp":1761720682780,"version":"build-2065373602"},"reference-count":27,"publisher":"CSIRO Publishing","issue":"5","license":[{"start":{"date-parts":[[2025,5,27]],"date-time":"2025-05-27T00:00:00Z","timestamp":1748304000000},"content-version":"vor","delay-in-days":1383,"URL":"https:\/\/doi.org\/10.1071\/journalslicense"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,3,11]]},"abstract":"<jats:p>Philippine crocodiles Crocodylus mindorensis are critically endangered due to agricultural and fishing threats that have severely fragmented their habitat and population in the Philippines. Captive management plans are important to safeguard against their extinction, but the current population in US zoos is small, and breeding is hampered by the slow growth of this species and the danger of introducing differently sized animals for breeding. There is little information regarding the sperm characteristics of crocodilians, and none for Philippine crocodiles. In this study, we sought to characterise sperm production in the male Philippine crocodile (n = 1) by performing voluntary (without sedation or restraint) collections (n = 181) over a 3.5-year period. Peak sperm production in this individual occurs from January to July, when the mean (\u00b1s.e.m.) total number of spermatozoa recovered was 10.2 \u00d7 106 \u00b1 3.8 \u00d7 106 (n = 104), compared with 0.3 \u00d7 106 \u00b1 0.2 \u00d7 106 (n = 71) for all other months of the year. Analysis of sperm morphology indicated that 15.9% of spermatozoa exhibited normal morphology. A bent tail was the most common abnormality (48.2%) observed. Understanding the basic reproductive biology of the male Philippine crocodile will facilitate the development of artificial reproductive technologies to improve captive propagation and genetic management of this species.<\/jats:p>","DOI":"10.1071\/rd21016","type":"journal-article","created":{"date-parts":[[2021,8,12]],"date-time":"2021-08-12T23:13:55Z","timestamp":1628810035000},"page":"410-416","source":"Crossref","is-referenced-by-count":1,"title":["Characterisation of sperm production and morphology in the male Philippine crocodile Crocodylus mindorensis via voluntary behavioural training"],"prefix":"10.1071","volume":"34","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5168-3417","authenticated-orcid":true,"given":"Shelley E. S.","family":"Sandmaier","sequence":"first","affiliation":[{"name":"AOmaha\u2019s Henry Doorly Zoo and Aquarium, 3701\u2009S. 10th Street, Omaha, NE 68107, USA."},{"name":"BCorresponding author. Email: shelley.sandmaier@omahazoo.com"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teresa","family":"Shepard","sequence":"additional","affiliation":[{"name":"AOmaha\u2019s Henry Doorly Zoo and Aquarium, 3701\u2009S. 10th Street, Omaha, NE 68107, USA."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andy","family":"Reeves","sequence":"additional","affiliation":[{"name":"AOmaha\u2019s Henry Doorly Zoo and Aquarium, 3701\u2009S. 10th Street, Omaha, NE 68107, USA."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kaytlin","family":"Bohr","sequence":"additional","affiliation":[{"name":"AOmaha\u2019s Henry Doorly Zoo and Aquarium, 3701\u2009S. 10th Street, Omaha, NE 68107, USA."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jessi","family":"Krebs","sequence":"additional","affiliation":[{"name":"AOmaha\u2019s Henry Doorly Zoo and Aquarium, 3701\u2009S. 10th Street, Omaha, NE 68107, USA."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jason R.","family":"Herrick","sequence":"additional","affiliation":[{"name":"AOmaha\u2019s Henry Doorly Zoo and Aquarium, 3701\u2009S. 10th Street, Omaha, NE 68107, USA."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"67","published-online":{"date-parts":[[2021,8,13]]},"reference":[{"key":"2025102820242681000_R1","first-page":"513","article-title":"Assisted reproduction in alligators: physical and morphological characterization of spectacled caiman semen Caiman crocodilus Linnaeus, 1758.","volume":"5","author":"Assump\u00e7\u00e3o","year":"2017","journal-title":"Int. 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