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Diversity of selected groups of intestinal protists in cockroaches (Blattodea excl. Isoptera)
Kotyk, Michael ; Čepička, Ivan (advisor) ; Modrý, David (referee) ; Fiala, Ivan (referee)
This thesis addresses the rather neglected diversity of protists inhabiting the anoxic environment of the hindgut of cockroaches (Blattodea excluding Isoptera). I have examined the composition of the eukaryotic hindgut biota of over 200 cockroach species, with a detailed focus on four selected groups of protists: parabasalids (Metamonada, Parabasalia), oxymonads (Metamonada, Preaxostyla, Oxymonadida), ciliates (Alveolata, Ciliophora), and gregarines (Alveolata, Apicomplexa, Eugregarinorida). The results reveal a significant and so far almost unknown diversity of cockroach metamonads. The oxymonads are mostly represented by small polymastigids of the genus Monocercomonoides and the newly described genus Blattamonas. An exception is the discovery of what is, to date, only the second representative of the genus Streblomastix. The majority of the identified parabasalids belong to either the order Hypotrichomonadida or Honigbergiellida. Here the study takes a slight detour to explore the diversity of honigbergiellids as well as other groups of trichomonads inhabiting a somewhat different anoxic environment, namely aquatic sediments. Here, previously unknown diversity of parabasalids is also found. Our findings include the description of a new parabasalid order, Pimpavickida. Other investigated organisms...
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Trypanosomes transmitted by mosquitoes: occurrence in hosts, transmission, and specificity
Kulich Fialová, Magdaléna ; Svobodová, Milena (advisor) ; Bernotienė, Rasa (referee) ; Modrý, David (referee)
7 Abstract Trypanosomes (Trypanosoma, Kinetoplastea) are dixenous blood protists that require not only a vertebrate host but also a blood-feeding invertebrate to complete their life cycle. Infection of vertebrates can be asymptomatic, but on the other hand can cause serious diseases affecting lives of humans and animals. Thus, researchers usually focus on Trypanosoma species causing Chagas disease and sleeping sickness in humans or nagana and surra in animals, and on their vectors: tsetse flies and kissing bugs. However, mosquitoes are able to transmit trypanosomes as well, specifically, avian trypanosomes and probably mammalian trypanosomes from the T. theileri group. Nevertheless, the role of mosquitoes in the life cycle of trypanosomes has substantial gaps, which are focused in this dissertation. Within the experimental work, it has been demonstrated that mosquitoes of the genus Culex are susceptible hosts of two species of avian trypanosomes: T. thomasbancrofti and T. tertium n. sp. On the other hand, Culex mosquitoes were unsuitable hosts for T. theileri, while the genus Aedes and surprisingly even sand flies (Phlebotomus perniciosus) turned up to be competent vectors. All investigated trypanosomes were able to develop within the guts of mosquitoes and were also found in their prediuretic liquid. This...
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Trypanosomes of green frogs (genus Pelophylax)
Poloprutská, Klára ; Votýpka, Jan (advisor) ; Modrý, David (referee)
Anuran trypanosomes are the first ever observed and described trypanosomes and Trypanosoma rotatorium from frogs of the genus Pelophylax is a type species of the genus Trypanosoma. Despite the early discovery, they are being neglected in terms of current descriptive studies when compared to other trypanosomes, although their diversity and prevalence in anurans are quite high. Anuran trypanosomes, which are significantly larger than their mammal relatives, display a high rate of polymorphism and pleiomorphism; however, without any explanations. Because of the amphibious nature of frogs, the vectors of anuran trypanosomes are both aquatic leeches and terrestrial bloodsucking insects. This thesis which aims at widening the scope of knowledge about this neglected group of trypanosomes focuses on trypanosomes from frogs of the genus Pelophylax found in Central Europe and the Balkan Peninsula. An overall prevalence of 71% was found in 981 individuals and a total of thirteen trypanosome species were detected, eight of which are new to science. Significantly higher diversity was found in frogs originating from the Balkan Peninsula; however, no host specificity of trypanosomes was detected. It was not possible to unambiguously prove the relationship between morphospecies and genospecies. On the contrary, I...
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Development of flagellates of the genus Porcisia and subgenus Mundinia in phlebotomine sand flies (Diptera: Psychodidae) and ceratopogonid midges (Diptera: Ceratopogonidae)
Bačíková, Dominika ; Sádlová, Jovana (advisor) ; Modrý, David (referee)
The main part of the thesis is focused on flagellates of the genus Porcisia, parasitizing Neotropical porcupines with unknown vectors. The development of two known species of this genus (P. deanei and P. hertigi) in two sand fly species (Lu. migonei, Lu. longipalpis) and biting midges C. sonorensis was studied using experimental infections. While P. hertigi did not survive defecation in females of either vector, P. deanei formed strong mature infections in 51-61% of Lu. longipalpis and in a smaller percentage in Lu. migonei (7 %) and C. sonorensis (7 %). Porcisia showed significantly smaller size than the control species L. infantum but formed the same morphological forms. The localization of P. deanei was exceptional; infections were detected predominantly in Malpighian tubules. Further experiments demonstrated the presence of P. deanei in the urine of Lu. longipalpis excreted during prediuresis and successful transmission of parasites to BALB/c mice by this unique route. Thus, Lu. longipalpis is a competent vector of P. deanei, but other vector species may be involved in transmission at endemic localities. A minor part is focused on the comparison of the morphology of two Mundinia species - L. martiniquensis and L. orientalis - during development in biting midges C. sonorensis and sand flies Ph....
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Leishmania of the subgenus Mundinia: genetical analysis and experimental infections of rodents and vectors.
Bečvář, Tomáš ; Sádlová, Jovana (advisor) ; Modrý, David (referee)
Leishmaniasis is a human and animal disease caused by digenetic parasites of the genus Leishmania, which is now divided into 4 subgenera - L. (Leishmania), L. (Viannia), L. (Sauroleishmania) and L. (Mundinia). Subgenus Mundinia was established in 2016 and consists of 5 species - L. enriettii and L. macropodum are parasites of wild mammals and L. martiniquensis, L. orientalis and unnamed L. sp. from Ghana are infectious to humans. Mundinia are geographically widely dispersed, their distribution covers all continents, except of Antarctica. Despite phlebotomine sand flies (Diptera: Psychodidae) also biting midges (Diptera: Ceratopogonidae) are supposed to be involved in transmission of these species, which is a unique feature for this subgenus. But there is little to no current information on natural reservoir hosts and vector species for any Mundinia species. In this thesis we tested possible vectors and potential model organisms (Guinea-pigs) and reservoir hosts of Mundinia species by experimental infections. We used 3 sand fly species sharing geographical distribution with respective Mundinia species and available in our laboratory for experimental infections. Sand flies from Australia had never been colonised so we used the permissive vector Lu. migonei for testing development of L. macropodum....
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Mosquitoes and biting midges as vectors in the Czech Republic
Rádrová, Jana ; Votýpka, Jan (advisor) ; Modrý, David (referee) ; Alten, Bülent (referee)
Insect is the largest and the most diverse class of animals and many species have significant impact to people and his activities, whether positive or negative. Since the late 19th century it is known, that bloodsucking insects can serve as vectors of pathogens, causative agents of many infection diseases. As climate change, the distribution and abundance of arthropods including bloodsucking insects can be affected. Emergence of new vector-borne diseases in Europe is likely to be among the most important effects of global changes. In recent years, several vector-borne diseases affecting humans and domestic animals have (re)emerged and spread in Europe with major health, ecological and socio-economical consequences. For example mosquito-borne West Nile virus affects human and animal health, as well. On the other hand, two newly emerged zoonosis, caused by Bluetongue and Schmallenberg viruses and transmitted by biting midges, affect mainly small domestic ruminants. In the frame of broader projects, two epidemiological and entomological surveys focused on mosquitoes and biting midges as possible vectors of West Nile virus, Bluetongue or Schmallenberg virus were carried out in the Czech Republic. New mosquito and biting midges species were recorded for the Czech Republic, the presence of West Nile...
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Biting midges and their patogens
Mračková, Marie ; Votýpka, Jan (advisor) ; Modrý, David (referee)
This thesis deals with biting midges of the genus Culicoides, which are tiny nematoceran insects belonging to the Diptera, and their parasites. Biting midges partake in transmissions of several parasitical organisms of various groups. Most notably, they are the vectors of several pathogenic viruses which might have a serious impact on livestock. However, the thesis deals with detection of parasites belonging to Trypanosomatids and Filarioids related to two independent biting midges collections - from the Czech Republic and from the Central African region. Apart from testing biting midges, there were carried out the tests on the occurrence of the same group of parasites within ruminant hoofed games in the Czech Republic. Our goal was to find out whether the same parasites occur with biting midges and their hosts (hoofed games) and whether biting midges could play a role as vectors. Biting midges are relatively overlooked group of haematophagous insects. Until recently, they had not been paid much attention, which changed with the spread of Bluetongue virus over Europe. This stimulated a widespread monitoring of biting midges in several European countries, including the Czech Republic. This helped to gain a large amount of data about the occurrence of biting midges near livestock. Nevertheless, there is no...
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Kinetoplastida of birds and bloodsucking Diptera: molecular characterization and life cycles
Zídková, Lenka ; Svobodová, Milena (advisor) ; Fiala, Ivan (referee) ; Modrý, David (referee)
We studied biodiversity of avian trypanosomes. We used newly obtained isolates of trypanosomatids from ornitophilic bloodsucking diptera (81) and from avian hosts (145). To investigate relationships among isolates we employed RAPD method and sequence analyses of SSU rRNA, eventually gGAPDH, 5S RNA or SL RNA. Additionally we used morphological characters; cell lengths and kinetoplast widths. All isolates obtained from biting midges belonged to monogenetic kinetoplastids. We described new species and a new genus Sergeia podlipaevi isolated from Culicoides (Oecacta) festivipennis a C. (O.) truncorum. We successfully infected with this species laboratory bred biting midge of different subgenus Culicoides (Monoculicoides) nubeculosus. We described isolate from Culicoides truncorum as new species Herpetomonas trimorpha. Its sister species was H. ztiplika described previously also from biting midges. We performed the most extensive study of biodiversity of avian trypanosomes based on comparison of wide spectrum of isolates obtained from different hosts. We confirmed that avian trypanosomes are polyphyletic and form three independent lineages within the genus Trypanosoma. We identified at least 11 species of avian trypanosomes. We found that ornitophilic mosquitoes belong among important vectors of avian...
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