{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T18:19:29Z","timestamp":1787941169527,"version":"build-2784847793"},"reference-count":31,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T00:00:00Z","timestamp":1787875200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    A unique clinical syndrome characterized by polyphasic rhabdomyositis associated with\n                    <jats:italic>Sarcocystis neurona<\/jats:italic>\n                    has been reported in both free-ranging and managed care California sea lions (CSLs;\n                    <jats:italic>Zalophus californianus<\/jats:italic>\n                    ). The pathogenesis of this disease is poorly understood. Specific\n                    <jats:italic>S. neurona<\/jats:italic>\n                    genotypes have been associated with more severe sarcocystosis and mortality in other marine mammals; however,\n                    <jats:italic>S. neurona<\/jats:italic>\n                    genotypes infecting CSLs with rhabdomyositis have not yet been investigated. The objective of this study was to characterize genotypes of\n                    <jats:italic>S. neurona<\/jats:italic>\n                    from CSLs with rhabdomyositis and to compare these with genotypes described in other marine and terrestrial hosts. Archived skeletal muscle samples from 25 affected free-ranging CSLs were screened for\n                    <jats:italic>S. neurona<\/jats:italic>\n                    DNA using polymerase chain reaction (PCR) targeting a multi-copy locus (ITS1), followed by genotype characterization using a PCR-based multilocus sequence typing approach targeting six polymorphic loci. Among these 25 CSLs, 15 different\n                    <jats:italic>S. neurona<\/jats:italic>\n                    genotypes were identified. Of these, six have been previously identified in southern sea otters (\n                    <jats:italic>Enhydra lutris nereis<\/jats:italic>\n                    ) and\/or other hosts, but the remaining nine have not been reported in any host to date. This study, although limited in sample size, demonstrates a wide diversity of\n                    <jats:italic>S. neurona<\/jats:italic>\n                    genotypes infecting free-ranging CSLs affected with rhabdomyositis, some shared with other hosts in the region, but many others that appear to be unique to sea lions.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0357274","type":"journal-article","created":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T17:50:46Z","timestamp":1787939446000},"page":"e0357274","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular characterization of Sarcocystis neurona genotypes in California sea lions (Zalophus californianus) with polyphasic rhabdomyositis"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-9149-0760","authenticated-orcid":true,"given":"Alene G.","family":"Pohly","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7890-4833","authenticated-orcid":true,"given":"Devinn M.","family":"Sinnott","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Margaret E.","family":"Martinez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cara L.","family":"Field","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P\u00e1draig J.","family":"Duignan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2678-3851","authenticated-orcid":true,"given":"Karen","family":"Shapiro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,28]]},"reference":[{"issue":"2","key":"pone.0357274.ref001","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1016\/S0304-4017(03)00206-1","article-title":"Recent origins among ancient parasites","volume":"115","author":"L David Sibley","year":"2003","journal-title":"Vet Parasitol"},{"issue":"6","key":"pone.0357274.ref002","doi-asserted-by":"crossref","first-page":"1276","DOI":"10.1645\/0022-3395(2000)086[1276:COTLCO]2.0.CO;2","article-title":"Completion of the life cycle of Sarcocystis neurona","volume":"86","author":"JP Dubey","year":"2000","journal-title":"J Parasitol"},{"key":"pone.0357274.ref003","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/S0304-4017(00)00384-8","article-title":"A review of Sarcocystis neurona and equine protozoal myeloencephalitis (EPM)","volume":"95","author":"JP Dubey","year":"2001","journal-title":"Vet Parasitol"},{"issue":"3","key":"pone.0357274.ref004","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1016\/S0304-4017(96)01112-0","article-title":"Experimental induction of equine protozoal myeloencephalitis in horses using Sarcocystis sp. sporocysts from the opossum (Didelphis virginiana)","volume":"68","author":"CK Fenger","year":"1997","journal-title":"Vet Parasitol"},{"key":"pone.0357274.ref005","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.vetpar.2015.01.026","article-title":"An update on Sarcocystis neurona infections in animals and equine protozoal myeloencephalitis (EPM)","volume":"209","author":"JP Dubey","year":"2015","journal-title":"Vet Parasitol"},{"key":"pone.0357274.ref006","first-page":"319","article-title":"Chapter 40: Tissue cyst forming coccidia of marine mammals","author":"M Miller","journal-title":"Zoo and Wild Animal Medicine: Current Therapy. 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