{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T15:14:46Z","timestamp":1772118886871,"version":"3.50.1"},"reference-count":59,"publisher":"Wiley","issue":"18","license":[{"start":{"date-parts":[[2021,7,22]],"date-time":"2021-07-22T00:00:00Z","timestamp":1626912000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"DOI":"10.13039\/501100001343","name":"University of Pretoria","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001343","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["analyticalsciencejournals.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Rapid Comm Mass Spectrometry"],"published-print":{"date-parts":[[2021,9,30]]},"abstract":"<jats:sec>\n                    <jats:title>Rationale<\/jats:title>\n                    <jats:p>\n                      The diet of wild Nile crocodiles (\n                      <jats:styled-content style=\"fixed-case\">\n                        <jats:italic>Crocodylus niloticus<\/jats:italic>\n                      <\/jats:styled-content>\n                      ) is difficult to assess because they are cryptic and nocturnal predators that are extremely sensitive to disturbance by observers, and stomach content analysis is challenging, especially in large specimens. Stable light isotope analysis provides a means of assessing their diet, but diet\u2010to\u2010tissue discrimination factors have yet to be established for the species.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      Isotope ratio (\n                      <jats:sup>15<\/jats:sup>\n                      N\/\n                      <jats:sup>14<\/jats:sup>\n                      N and\n                      <jats:sup>13<\/jats:sup>\n                      C\/\n                      <jats:sup>12<\/jats:sup>\n                      C expressed as \u03b4\n                      <jats:sup>15<\/jats:sup>\n                      N and \u03b4\n                      <jats:sup>13<\/jats:sup>\n                      C) analyses of scutes, claws, and blood of farmed crocodiles of different sizes were compared with the isotope values of their lifelong diet, which comprises chickens from a single supplier.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Systematic size dependence in the diet\u2010to\u2010tissue discrimination factors for scute collagen, scute keratin, and claw keratin is described in regression relationships against the snout to vent length. Fixed values are presented for erythrocytes and blood plasma because blood was not sampled from juveniles.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The diet\u2010to\u2010tissue discrimination factors help assess the diet of wild crocodiles. The diet of crocodiles from Lake Flag Boshielo shows a clear ontogenic shift, as has been seen in other studies, and the results strongly indicate a dependence on the terrestrial food web rather than a fish diet. That this population may exploit a terrestrial diet highlights potential conflicts for conserving Nile crocodiles outside protected areas.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/rcm.9159","type":"journal-article","created":{"date-parts":[[2021,7,5]],"date-time":"2021-07-05T14:19:48Z","timestamp":1625494788000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Ontogenetic dependence of Nile crocodile (\n                    <scp>\n                      <i>Crocodylus niloticus<\/i>\n                    <\/scp>\n                    ) isotope diet\u2010to\u2010tissue discrimination factors"],"prefix":"10.1002","volume":"35","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8573-8626","authenticated-orcid":false,"given":"Stephan","family":"Woodborne","sequence":"first","affiliation":[{"name":"Tandem &amp; AMS Laboratory iThemba LABS  Johannesburg South Africa"},{"name":"Stable Isotope Laboratory, Mammal Research Institute University of Pretoria  Pretoria South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6870-5494","authenticated-orcid":false,"given":"Hannes","family":"Botha","sequence":"additional","affiliation":[{"name":"Mpumalanga Tourism and Parks Agency Scientific Services  Nelspruit South Africa"},{"name":"Department of Biodiversity University of Limpopo  Sovenga South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3799-9239","authenticated-orcid":false,"given":"David","family":"Huchzermeyer","sequence":"additional","affiliation":[{"name":"Sterkspruit Veterinary Clinic  Lydenburg South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2132-7251","authenticated-orcid":false,"given":"Jan","family":"Myburgh","sequence":"additional","affiliation":[{"name":"Department of Paraclinical Sciences, Faculty of Veterinary Science University of Pretoria  Onderstepoort South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2164-4900","authenticated-orcid":false,"given":"Grant","family":"Hall","sequence":"additional","affiliation":[{"name":"Stable Isotope Laboratory, Mammal Research Institute University of Pretoria  Pretoria South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6891-1893","authenticated-orcid":false,"given":"Albert","family":"Myburgh","sequence":"additional","affiliation":[{"name":"Department of Zoology and Entomology University of Pretoria  Pretoria South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2021,7,22]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.ecolsys.39.110707.173545"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00442-003-1382-5"},{"key":"e_1_2_8_4_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2656.2011.01830.x"},{"key":"e_1_2_8_5_1","doi-asserted-by":"publisher","DOI":"10.1086\/706071"},{"key":"e_1_2_8_6_1","doi-asserted-by":"publisher","DOI":"10.1038\/scientificamerican0476-114"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.2307\/4797"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1670\/07-1071.1"},{"key":"e_1_2_8_9_1","doi-asserted-by":"publisher","DOI":"10.1080\/10256016.2012.667808"},{"key":"e_1_2_8_10_1","doi-asserted-by":"publisher","DOI":"10.4314\/wsa.v35i5.49193"},{"key":"e_1_2_8_11_1","doi-asserted-by":"publisher","DOI":"10.1002\/aqc.1175"},{"key":"e_1_2_8_12_1","doi-asserted-by":"publisher","DOI":"10.1638\/2012-0264R.1"},{"key":"e_1_2_8_13_1","unstructured":"HeathR ColemanT EngelbrechtJ.Water quality overview and literature review of the ecology of the Olifants River.WRC (Water research Commision of South Africa). 2010;Report No. TT452\/10."},{"key":"e_1_2_8_14_1","doi-asserted-by":"publisher","DOI":"10.1002\/aqc.1132"},{"key":"e_1_2_8_15_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cbpa.2009.09.025"},{"key":"e_1_2_8_16_1","doi-asserted-by":"publisher","DOI":"10.1890\/ES12-00170.1"},{"key":"e_1_2_8_17_1","doi-asserted-by":"publisher","DOI":"10.1111\/jfd.12633"},{"key":"e_1_2_8_18_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2761.2011.01267.x"},{"key":"e_1_2_8_19_1","first-page":"126","article-title":"Eight additional cases of pansteatitis (\" yellow fat\") in cats fed canned red tuna","volume":"137","author":"Griffiths RC","year":"1960","journal-title":"J am Vet Med Assoc"},{"key":"e_1_2_8_20_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2761.1979.tb00145.x"},{"key":"e_1_2_8_21_1","doi-asserted-by":"crossref","unstructured":"HuchzermeyerFW.Crocodiles: biology husbandry and diseases. 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