Vectors of avian trypanosomes and prevalence in Passerines

Tato bakalářská práce má za cíl shrnout poznatky o vývoji ptačích trypanosom ve vektorech a o prevalenci trypanosom v ptácích. Trypanosomy jsou dvou hostitelští parazitičtí prvoci žijící v krvi obratlovců a v bezobratlých vektorech. Množení ptačích trypanosom probíhá převážně ve vektoru, kde byla již v polovině minulého století pozorována různá vývojová stadia, a to hlavně promastigoti, epimastigoti a metacykličtí trypomastigoti. V krvi ptáků se vyskytují krevní trypomastigoti. Vektory ptačích trypanosom jsou zástupci čeledí Ceratopogonidae, Culicidae, Simuliidae, Hippoboscidae a Dermanyssidae. Zatímco ve vektoru bylo dělení trypanosom pozorováno opakovaně, v ptácích je pozorováno jen zřídka. Údaje o prevalenci v ptácích se velmi liší, což je dáno převážně použitou metodou detekce trypanosom v krvi ptáků. Zatímco dříve se používaly k detekci trypanosom hlavně roztěry krve, dnes se přechází k citlivějším metodám jako PCR nebo kultivace trypanosom.The aim of this bachelor thesis is to summarize the knowledge about the development of avian trypanosomes in the vector, and about their prevalence in avian hosts. Trypanosomes are dixenous parasitic protists. They live in the bloodstream of vertebrates and in invertebrate vectors. Replication of avian trypanosomes occurs mainly in the vector. Promastigote, epimastigote and metacyclic trypomastigote stages were observed in the vector already in the 1950s. In avian blood, bloodstream trypomastigotes occur. The vectors of avian trypanosomes are members of families Ceratopogonidae, Culicidae, Simuliidae, Hippoboscidae and Dermanyssidae. Although replication of trypanosomes has been seen in the vector, observations of division in birds are scarse. Results concerning prevalence of trypanosomes in birds considerably differ between different studies. This is mostly due to differences in methods used to detect trypanosomes from avian blood. Whereas detection from blood smears was used in the past, nowadays, more sensitive methods have been introduced, such as PCR or cultivation of trypanosome.Katedra parazitologieDepartment of ParasitologyFaculty of SciencePřírodovědecká fakult

The role of hippoboscids in avian trypanosomes transmission

Cílem této diplomové práce bylo zmapovat výskyt ptačích druhů klošů v České republice, objasnit, jaké linie ptačích trypanosom tito kloši přenášejí, a prozkoumat specificitu vůči vektorům u trypanosom dříve izolovaných z klošů. Během let 2017 - 2018 byly z pěvců odchyceny tyto ptačí kloši Ornithomya avicularia (91), O. biloba (267), O. fringillina (45), Ornithoica turdi (6), Stenepteryx hirundinis (1) a Ornithophila metallica (1). Potvrdila se hostitelská specifita vůči vlaštovkovitým u druhů O. biloba a S. hirundinis, Ostatní druhy klošů se vyskytovaly na tažných i stálých ptácích. Fylogenetická analýza genu pro cytochrom c oxidázu I, která zahrnovala i dříve necharakterizovaný druh O. metallica, odhalila příbuznost tohoto druhu s O. turdi. Ptačí trypanosomy byly detekovány u O. biloba (prevalence 20 %), O. avicularia (prevalence 8 %) a O. fringillina (prevalence 4 %). Všechny trypanosomy izolované z klošů patřily do skupiny ptačích trypanosom corvi-culicavium. Fylogenetická analýza trypanosom potvrdila výskyt pěti dříve popsaných linií této skupiny, čtyři izoláty z ptačí krve tvořily dvě nové bazální skupiny. Většina sekvencí trypanosom izolovaných z klošů tvořila sesterskou skupinu dříve popsaným liniím. Specifita vůči vektorům u jednotlivých linií ptačích trypanosom izolovaných z klošů byla zjišťována...The aim of this thesis was to map the presence of avian hippoboscids in Czechia, clarify which lineages of avian trypanosomes are transmitted by them, and to test vector specificity of the trypanosomes that were isolated from louse flies earlier. In the years 2017 - 2018 we found 7 species of louse flies, namely Ornithomya avicularia (91), O. biloba (267), O. fringillina (45), Ornithoica turdi (6), Stenepteryx hirundinis (1) and Ornithophila metallica (1). The specificity of O. biloba and S. hirundinis toward Hirudinidae was confirmed. The other louse fly species were found on both migrant and resident birds. The phylogenetic analysis of gene for cytochrome c oxidase I which contained a newly characterised species O. metallica revealed that it is related to O. turdi. Avian trypanosomes were present in the following species: O. biloba (prevalence 20 %), O. avicularia (8 %), a O. fringillina (4 %). All trypanosome sequences from hippoboscids belonged to the avian trypanosome group corvi-culicavium. Phylogenetic analysis of trypanosome sequences confirmed the presence of five lineages of avian trypanosomes. Four trypanosome sequences from birds formed two new basal clades. Most of the trypanosome sequences from hippoboscids formed a sister group to the previously described lineages. The vector specificity of...Katedra parazitologieDepartment of ParasitologyPřírodovědecká fakultaFaculty of Scienc

Avian Louse Flies and Their Trypanosomes: New Vectors, New Lineages and Host–Parasite Associations

Louse flies (Hippoboscidae) are permanent ectoparasites of birds and mammals. They have a cosmopolitan distribution with more than 200 described species. The aim of this study was to reveal host–vector–parasite associations between louse flies, birds, and trypanosomes. A total of 567 louse fly specimens belonging to 7 species were collected from birds at several localities in Czechia, including the rare species Ornithophila metallica and Ornithoica turdi. There was a significant difference in the occurrence of Ornithomya avicularia and Ornithomya fringillina on bird hosts according to their migratory status, O. fringillina being found more frequently on long-distance migrants. Trypanosomes were found in four species, namely, Ornithomya avicularia, O. fringillina, O. biloba, and Ornithoica turdi; the later three species are identified in this paper as natural trypanosome vectors for the first time. The prevalence of trypanosomes ranged between 5 and 19%, the highest being in O. biloba and the lowest being in O. fringillina. Phylogenetic analysis of the SSU rRNA gene revealed that a vast majority of trypanosomes from hippoboscids belong to the avian T. corvi/culicavium group B. Four new lineages were revealed in group B, with louse flies being probable vectors for some of these trypanosome lineages. We also confirmed the transcontinental distribution of several trypanosome lineages. Our results show that hippoboscids of several genera are probable vectors of avian trypanosomes

Vectors of avian trypanosomes and prevalence in Passerines

The aim of this bachelor thesis is to summarize the knowledge about the development of avian trypanosomes in the vector, and about their prevalence in avian hosts. Trypanosomes are dixenous parasitic protists. They live in the bloodstream of vertebrates and in invertebrate vectors. Replication of avian trypanosomes occurs mainly in the vector. Promastigote, epimastigote and metacyclic trypomastigote stages were observed in the vector already in the 1950s. In avian blood, bloodstream trypomastigotes occur. The vectors of avian trypanosomes are members of families Ceratopogonidae, Culicidae, Simuliidae, Hippoboscidae and Dermanyssidae. Although replication of trypanosomes has been seen in the vector, observations of division in birds are scarse. Results concerning prevalence of trypanosomes in birds considerably differ between different studies. This is mostly due to differences in methods used to detect trypanosomes from avian blood. Whereas detection from blood smears was used in the past, nowadays, more sensitive methods have been introduced, such as PCR or cultivation of trypanosome

The role of hippoboscids in avian trypanosomes transmission

The aim of this thesis was to map the presence of avian hippoboscids in Czechia, clarify which lineages of avian trypanosomes are transmitted by them, and to test vector specificity of the trypanosomes that were isolated from louse flies earlier. In the years 2017 - 2018 we found 7 species of louse flies, namely Ornithomya avicularia (91), O. biloba (267), O. fringillina (45), Ornithoica turdi (6), Stenepteryx hirundinis (1) and Ornithophila metallica (1). The specificity of O. biloba and S. hirundinis toward Hirudinidae was confirmed. The other louse fly species were found on both migrant and resident birds. The phylogenetic analysis of gene for cytochrome c oxidase I which contained a newly characterised species O. metallica revealed that it is related to O. turdi. Avian trypanosomes were present in the following species: O. biloba (prevalence 20 %), O. avicularia (8 %), a O. fringillina (4 %). All trypanosome sequences from hippoboscids belonged to the avian trypanosome group corvi-culicavium. Phylogenetic analysis of trypanosome sequences confirmed the presence of five lineages of avian trypanosomes. Four trypanosome sequences from birds formed two new basal clades. Most of the trypanosome sequences from hippoboscids formed a sister group to the previously described lineages. The vector specificity of..

Avian Louse Flies and Their Trypanosomes: New Vectors, New Lineages and Host–Parasite Associations

Louse flies (Hippoboscidae) are permanent ectoparasites of birds and mammals. They have a cosmopolitan distribution with more than 200 described species. The aim of this study was to reveal host–vector–parasite associations between louse flies, birds, and trypanosomes. A total of 567 louse fly specimens belonging to 7 species were collected from birds at several localities in Czechia, including the rare species Ornithophila metallica and Ornithoica turdi. There was a significant difference in the occurrence of Ornithomya avicularia and Ornithomya fringillina on bird hosts according to their migratory status, O. fringillina being found more frequently on long-distance migrants. Trypanosomes were found in four species, namely, Ornithomya avicularia, O. fringillina, O. biloba, and Ornithoica turdi; the later three species are identified in this paper as natural trypanosome vectors for the first time. The prevalence of trypanosomes ranged between 5 and 19%, the highest being in O. biloba and the lowest being in O. fringillina. Phylogenetic analysis of the SSU rRNA gene revealed that a vast majority of trypanosomes from hippoboscids belong to the avian T. corvi/culicavium group B. Four new lineages were revealed in group B, with louse flies being probable vectors for some of these trypanosome lineages. We also confirmed the transcontinental distribution of several trypanosome lineages. Our results show that hippoboscids of several genera are probable vectors of avian trypanosomes