{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T18:18:16Z","timestamp":1784830696931,"version":"3.55.0"},"reference-count":38,"publisher":"Inter-Research Science Center","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Dis. Aquat. Org."],"published-print":{"date-parts":[[2020,4,30]]},"abstract":"<jats:p><jats:italic>Crassicauda<\/jats:italic> spp. (Nematoda) infest the cranial sinuses of several odontocetes, causing diagnostic trabecular osteolytic lesions. We examined skulls of 77 Indian Ocean humpback dolphins <jats:italic>Sousa plumbea<\/jats:italic> and 69 Indo-Pacific bottlenose dolphins <jats:italic>Tursiops aduncus<\/jats:italic>, caught in bather-protecting nets off KwaZulu-Natal (KZN) from 1970-2017, and skulls of 6 <jats:italic>S. plumbea<\/jats:italic> stranded along the southern Cape coast in South Africa from 1963-2002. Prevalence of cranial crassicaudiasis was evaluated according to sex and cranial maturity. Overall, prevalence in <jats:italic>S. plumbea<\/jats:italic> and <jats:italic>T. aduncus<\/jats:italic> taken off KZN was 13 and 31.9%, respectively. Parasitosis variably affected 1 or more cranial bones (frontal, pterygoid, maxillary and sphenoid). No significant difference was found by gender for either species, allowing sexes to be pooled. However, there was a significant difference in lesion prevalence by age, with immature <jats:italic>T. aduncus<\/jats:italic> 4.6 times more likely affected than adults, while for <jats:italic>S. plumbea<\/jats:italic>, the difference was 6.5-fold. As severe osteolytic lesions are unlikely to heal without trace, we propose that infection is more likely to have a fatal outcome for immature dolphins, possibly because of incomplete bone development, lower immune competence in clearing parasites or an over-exuberant inflammatory response in concert with parasitic enzymatic erosion. Cranial osteolysis was not observed in mature males (18 <jats:italic>S. plumbea,<\/jats:italic> 21 <jats:italic>T. aduncus<\/jats:italic>), suggesting potential cohort-linked immune-mediated resistance to infestation. <jats:italic>Crassicauda<\/jats:italic> spp. may play a role in the natural mortality of <jats:italic>S. plumbea<\/jats:italic> and <jats:italic>T. aduncus<\/jats:italic>, but the pathogenesis and population level impact remain unknown.<\/jats:p>","DOI":"10.3354\/dao03468","type":"journal-article","created":{"date-parts":[[2020,3,5]],"date-time":"2020-03-05T09:39:53Z","timestamp":1583401193000},"page":"93-102","source":"Crossref","is-referenced-by-count":14,"title":["Cranial crassicaudiasis in two coastal dolphin species from South Africa is predominantly a disease of immature individuals"],"prefix":"10.3354","volume":"139","author":[{"given":"MF","family":"Van Bressem","sequence":"first","affiliation":[{"name":"Cetacean Conservation Medicine Group, Peruvian Centre for Cetacean Research, Museo de Delfines, Lima 20, Peru"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P","family":"Duignan","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, The Marine Mammal Center, 2000 Bunker Road, Sausalito, California 94965, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"JA","family":"Raga","sequence":"additional","affiliation":[{"name":"Marine Zoology Unit, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, PO Box 22085, 46071 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"K","family":"Van Waerebeek","sequence":"additional","affiliation":[{"name":"Cetacean Conservation Medicine Group, Peruvian Centre for Cetacean Research, Museo de Delfines, Lima 20, Peru"},{"name":"Center for Chinese White Dolphin Research and Conservation, Beijing Institute of Technology at Zhuhai, 6 Jinfeng Road, Zhuhai City, 51900 Guangdong, PR China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"N","family":"Fraijia-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Marine Zoology Unit, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, PO Box 22085, 46071 Valencia, Spain"},{"name":"Department of Life Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S","family":"Pl\u00f6n","sequence":"additional","affiliation":[{"name":"Earth Stewardship Science Research Institute-African Earth Observatory Network (AEON), Nelson Mandela University, South Campus, Port Elizabeth 6031, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1913","reference":[{"key":"Ref1","doi-asserted-by":"publisher","DOI":"10.1016\/j.biocon.2012.10.007"},{"key":"Ref2","doi-asserted-by":"publisher","DOI":"10.1578\/AM.39.4.2013.397"},{"key":"Ref3","doi-asserted-by":"publisher","DOI":"10.3354\/dao02694"},{"key":"Ref4","unstructured":"Best PB (2007) Whales and dolphins of the southern African subregion. 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