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Influence of avian Plasmodium on their hosts
Dulavová, Kristýna ; Svobodová, Milena (advisor) ; Vinkler, Michal (referee)
Avian malaria parasites of the genus Plasmodium are unicellular (and intracellular) protozoans of the group Haemospororida, using a blood-sucking insect (mosquito) as a vector and a bird as a vertebrate host. The effects of this disease, together with avian pox, have greatly influenced endemic populations of Hawaiian birds after introduction of a suitable vector to the islands by a human hand, leading to a drastic extinction of bird species; most of the remaining Hawaiian endemic species are now endangered. Apart from that, avian malaria is distributed nearly all over the world, infecting a variety of different hosts. This thesis is focused on the influence of avian malaria parasites mainly on their avian hosts. The most severe patologies caused by Plasmodium are associated with blood stages causing serious anemia in birds. More pathologies are connected with exoerythrocytic stages in the endothelial cells in various organs and are accompanied with external signs such as lethargy, respiratory distress, weakness, inappetence, sometimes weight loss and so on; different plasmodium species-bird host combinations have different outcomes. An interesting issue is the emerging tolerance against avian malaria in Hawaii Amakihi (Hemignathus virens), a species occupying low elevation areas of Hawaiian...
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