{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T12:35:42Z","timestamp":1789907742154,"version":"4.0.1"},"reference-count":23,"publisher":"Public Library of Science (PLoS)","issue":"10","license":[{"start":{"date-parts":[[2023,10,25]],"date-time":"2023-10-25T00:00:00Z","timestamp":1698192000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000199","name":"U.S. Department of Agriculture","doi-asserted-by":"publisher","award":["2017- 04619"],"award-info":[{"award-number":["2017- 04619"]}],"id":[{"id":"10.13039\/100000199","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100013432","name":"National Center for Veterinary Parasitology","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100013432","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007765","name":"Kansas State University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100007765","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ramsey Endowed Chair"}],"content-domain":{"domain":["www.plosntds.org"],"crossmark-restriction":false},"short-container-title":["PLoS Negl Trop Dis"],"abstract":"<jats:sec id=\"sec001\"><jats:title>Background<\/jats:title><jats:p><jats:italic>Toxocara canis<\/jats:italic>is a cosmopolitan parasite of dogs that is transmitted transplacentally to puppies resulting in widespread shedding of eggs in the environment. However, it is not clear if there are dominant parasite genotypes that are more common, pathogenic, or likely to be zoonotic.<\/jats:p><\/jats:sec><jats:sec id=\"sec002\"><jats:title>Methods\/principle findings<\/jats:title><jats:p>Sequences of mitochondrial<jats:italic>cox1<\/jats:italic>gene from adult worms were used to compare parasites from the United States with submitted sequences from parasites isolated from dogs in different countries. Our analysis revealed at least 55 haplotypes. While we expected the North American worms to form a distinct cluster, we found haplotypes of<jats:italic>T<\/jats:italic>.<jats:italic>canis<\/jats:italic>reported elsewhere existing in this population. Interestingly, combining the sequence data from our study with the available GenBank data, analysis of<jats:italic>cox1<\/jats:italic>sequences results in five distinct clades that are not geographically defined.<\/jats:p><\/jats:sec><jats:sec id=\"sec003\"><jats:title>Conclusions<\/jats:title><jats:p>The five clades of<jats:italic>T<\/jats:italic>.<jats:italic>canis<\/jats:italic>revealed in this study potentially have unique life histories, traits, or host preferences. Additional investigation is needed to see if these distinct clades represent cryptic species with clinically useful attributes or genotypes with taxonomic value. Evaluation of common mitochondrial genes may reveal distinct populations of zoonotic<jats:italic>T<\/jats:italic>.<jats:italic>canis<\/jats:italic>.<\/jats:p><\/jats:sec>","DOI":"10.1371\/journal.pntd.0011665","type":"journal-article","created":{"date-parts":[[2023,10,25]],"date-time":"2023-10-25T17:30:37Z","timestamp":1698255037000},"page":"e0011665","update-policy":"https:\/\/doi.org\/10.1371\/journal.pntd.corrections_policy","source":"Crossref","is-referenced-by-count":5,"title":["Haplotypic analysis of cox1 from Toxocara canis demonstrates five distinct clades that are not geographically defined"],"prefix":"10.1371","volume":"17","author":[{"given":"Katy A.","family":"Martin","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeba R. 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