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dc.contributor.advisorSmit, Nico
dc.contributor.advisorDavies Russell, Angela
dc.contributor.advisorHeideman, Neil
dc.contributor.authorVan As, Johann
dc.date.accessioned2015-11-24T09:33:34Z
dc.date.available2015-11-24T09:33:34Z
dc.date.copyright2012-01
dc.date.issued2012-01
dc.date.submitted2012-01
dc.identifier.urihttp://hdl.handle.net/11660/1840
dc.description.abstractEnglish: The study of blood parasites of reptiles is a relatively new and unexplored field in South Africa. Therefore, the general aims of this research were to explore the haemoparasite fauna of cordylid lizards, Pseudocordylus melanotus, Pseudocordylus subviridis and Pseudocordylus langi, and especially to search for the definitive hosts and likely vectors of their haemogregarines. Surveys of lizard blood were conducted at various altitudinal gradients on the Sentinel Trail in the escarpment area of the Drakensberg, and at the top of Platberg, near Harrismith, both in the Free State. Five species of haemogregarines were identified, all suspected to belong to the genus Hepatozoon, and none was known from previously published records. These occurred in the blood of P. melanotus, P. langi and P. subviridis from the two disjunct study sites, and mostly were accompanied by other haemoparasites including a saurian malaria, so-called Sauroplasma, and filarial nematodes. Developmental stages of two of the Hepatozoon spp. were documented in the internal organs of P. melanotus and P. subviridis by means of light and confocal microscopy, histology, and transmission electron microscopy. Life stages were also observed in ectoparasitic lizard mites, by means of stained histological sections, and in stained squashes of mites and mosquitoes. Three species of experimentally reared mosquitoes were found to act as likely definitive hosts for Hepatozoon spp. of P. melanotus and P. subviridis, while wild caught Culex (Afroculex) lineata appeared to serve as a definitive host, and therefore possible vector for an Hepatozoon species of P. melanotus at the top of Platberg. A saurian malaria that appeared to have features of two previously described species was recorded in P. melanotus and P. subviridis. New locality records for so-called Sauroplasma and filarial nematodes were also documented for the three species of crag lizards. Some aspects of the fine structure of two haemogregarines, the Plasmodium sp. and so-called Sauroplasma infections were recorded for the first time in the erythrocytes of the Pseudocordylus spp. Differential leucocyte and thrombocyte counts were performed on the three crag lizard species and, with erythrocyte characteristics, compared with those of cordylid lizards in previous studies. Several types of leucocytes were characterized ultrastructurally, as well as by light microscopy, and attempts were made to correlate statistically leucocyte counts, and host and environmental data, with parasite loads. Finally, mites and mosquitoes associated with crag lizards were explored further as possible vectors of lizard haemoparasites, and studied using light and scanning electron microscopy.en_ZA
dc.description.abstractAfrikaans: Die bestudering van bloed parasiete van reptiele is ‘n relatiewe nuut en onbekende veld in Suid-Afrika. Dus was die algemene doelwit van hierdie navorsing om die bloed parasiet fauna van akkedisse in die Cordylidae, Pseudocordylus melanotus, Pseudocordylus subviridis en Pseudocordylus langi te ondersoek en veral die finale gashere en moontlike vektore op te spoor. Akkedis bloed is in die Vrystaat teen verskillende hoogtes versamel by die Sentinel voetslaanpad in die Drakensberg en bo-op Platberg naby Harrismith, wat afsonderlike geïsoleerde areas is. Vyf spesies haemogregarines is geïdentifiseer, waarvan almal klaarblyklik aan die genus Hepatozoon behoort en wat voorheen nog nie beskryf is nie. Hierdie haemogregarines het voorgekom in die bloed van P. melanotus, P. langi en P. subviridis en is gevind tesame met ander bloed parasiete, insluited akkedis malaria, sogenaamde Sauroplasma infeksies en filariale nematode. Die ontwikkelings-stadiums van twee Hepatozoon spp. in die interne organe van P. melanotus en P. subviridis is waargeneem deur middel van van lig, transmissie- en konfokale mikroskopie asook met behulp van histologiese tegnieke. Lewenssiklus-stadia in ektoparasitiese myte en muskiete is waargeneem deur middel van histologiese snitte asook in gekleurde preparate van myte en muskiete. Drie spesies eksperimenteel geteelde muskiete was heel moontlik die finale gashere van Hepatozoon spp. in P. melanotus en P. subviridis. Dit blyk of wilde muskiete Culex (Afroculex) lineata die finale gasheer en dus die vektor vir ‘n Hepatozoon sp. van P. melanotus op Platberg kon wees. ‘n Akkedis malaria met eienskappe van twee voorheen beskryfde spesies, is gevind in die bloed van P. melanotus en P. subviridis. Nuwe lokaliteits-rekords is opgeteken vir sogenaamde Sauroplasma en filariale nematood infeksies in hierdie gasheer spesies. Sommige aspekte van die fyn- struktuur van twee haemogregarines, die Plasmodium sp. asook die sogenaamde Sauroplasma infeksies in the eretrosiete van Pseudocordylus spp., is vir die eerste keer opgeteken. Differensiële leukosiet- en trombosiet-tellings is uitgevoer op die bloed van die drie gasheer spesies en, tesame met hul eretrosiet eienskappe, met dié van voorheen bestudeerde akkedisse vergelyk. Ultrastrukturiële eienskappe van verskeie soorte leukosiete is deur middel van lig mikroskopie vasgestel en daar is gepoog on leukosiet- tellings, gasheer en omgewings data met parasiet ladings te korreleer. Uiteindelik is myte en muskiete, wat geassosieërd met die akkedisse voorkom, verder met behulp van lig en skanderings-elektron mikroskopie ondersoek as moonglike vektore van akkedis bloed parasiete.af
dc.language.isoenen_ZA
dc.publisherUniversity of the Free Stateen_ZA
dc.subjectThesis (Ph.D. (Zoology and Entomology))--University of the Free State, 2012en_ZA
dc.subjectBlood -- Parasites -- Ecologyen_ZA
dc.subjectBlood -- Parasites -- Life cyclesen_ZA
dc.subjectSquamata -- South Africa -- Free Stateen_ZA
dc.subjectHaemoparasitesen_ZA
dc.subjectMorphologyen_ZA
dc.subjectCrag lizardsen_ZA
dc.subjectMosquitoesen_ZA
dc.subjectTaxonomyen_ZA
dc.subjectFinal hostsen_ZA
dc.subjectVectorsen_ZA
dc.titleEcology, taxonomy and possible life cycles of blood protozoans infecting crag lizards (Pseudocordylus spp.) from the eastern Free State highlandsen_ZA
dc.typeThesisen_ZA
dc.rights.holderUniversity of the Free Stateen_ZA


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