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Migration and pathogenicity of neurotropic helminths
Pech, Václav ; Chanová, Marta (referee) ; Horák, Petr (advisor)
A neurotropism of helminths can be observed in their intermediate, paratenic and definitive hosts. Neurotropic helminths migrate through the nervous tissue, where maturation and reproduction can take place. The neurotropic helminths can be found in the family of trematodes (Diplostomum baeri, D. phoxini, Ornithodiplostomum ptychocheilus, Trichobilharzia regenti), cestodes (Taenia multiceps, T. solium) and nematodes (Angiostrongylus cantonensis, Elaphostrongylus cervi, Parelaphostronglus tenuis, Baylisascaris procyonis). Presence of these helminths in the nervous tissue can (usually with contribution of the immune system) lead to neurological or other pathological changes: the infected hosts can even die. Some of the neurotropic helminths (A. cantonensis, B. procyonis, T. solium, T. multiceps) can infect humans as well.
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The role of humoral factors in the snail immune response against schistosomes
Košťáková, Monika ; Dvořák, Jiří (referee) ; Horák, Petr (advisor)
Digenetic trematodes such as Schistosoma mansoni use molluscs, mainly Gastropoda in their life cycle, as their intermediary hosts. e internal defense system (IDS) of snails is composed of immune cells called hemocytes, which are the main effectors and act jointly with soluble components. Humoral factors could in uence directly the parasite's larval stage, the activity of hemocytes and also may serve in recognition of the parasite. Lectins are considered to be the main component of humoral immunity. ey have a primary role in non-self recognition. Other protein group with lectin-like activity called FRePs was found in Biomphalaria glabrata. eir unique structure contains a brinogen and an immunoglobulin-like domain. Cytokine-like molecules may play very important role in defense as well. Many molecules are present in hemolymph and their levels change during infection. e response to parasitosis is therefore very complex and still awaits further clari cation.
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Parasitic diseases of Australian parrot species
Rasochová, Karolína ; Jankovská, Ivana (advisor) ; Husák, Tomáš (referee)
Australian parrot species can host many species of parasites. Parasitic diseases affects both parrots kept in captivity and living wild. This work is compiled as a literary review and provides a summary of most parasites with confirmed presence at the Australian species of parrots. Many parasites species have been detected recently. The presence of new species is confirmed also for parrots kept in Central Europe (coccidia Sarcocystis
calchasi) including the Czech Republic (parasitic protozoa Leucocytozoon spp., roundworm Ascaridia platyceri).
Parasitic infections may be detected trough examining samples from living parrots (feces, blood, tissues) or trough necropsy of died individuals (histopatology). In psittacines, protozal infections have been described (phylum Metamonada and Apicomplexa). Giardiasis, coccidiosis, cryptosporidiosis and blood parasites (Plasmodium spp., Leucocytozoon spp., Haemoproteus spp.) are among the most frequent. Australian parrot species are among the most frequent hosts of nematodes roundworms (Ascaridia spp.) and capillaries (Capillaria spp.). Regarding the strain Fungi, presence of Encephalitozoon hellem which causes microsporidiosis which primarily occurs in humans with acquired immunodeficiency has also been identified in psittacines. This makes it a potentially zoonotic disease. As of the ectoparasites, those most important representatives from the variety of species of parasitic mites and insects are mentioned. The life cycle of the parasites, their pathogenicity, ways of transmission, clinical signs in affected individuals, diagnosis and treatment options have been described.
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Helminths of the European otter
Seemannová, Kateřina ; Vadlejch, Jaroslav (advisor) ; Lukáš, Lukáš (referee)
The target of this study was to explore a distribution and prevalence of parasitic helmints in population of wild European otters in the Czech Republic. For this purpose organization ALKA wildlife o.p.s. provided 15 cadavers of these animals. This gained experimental material was consequently subjected to a detailed parasitical examination. All examinations and analises were made in the parazitical laboratory of Department of Zoology and Fishers, Faculty of Agrobiology, food and natural resources in Czech University of Life Sciences in Prague. The discovered parazitic organisms were subsequently isolated and determined. This autopsy showed the occurrence of parasitic flukes of genus Metorchis. Prevalence was counted 13.33 % (two positive samples from all fifteen samples). In the first sample, there were found 17 flukes, in the second sample, there were found 11 flukes. The place of discovery of this samples was southern Bohemia. The occurence of other expected representers of tapeworms, roundworms and acanthocephala were not confirmed. Results can be disorted because of low number of examined biological material. But getting bigger amount of material is a problem because the European otters are protected by law.
The results show that in population of wild European otters occur parasitic flukes of genus Metorchis. Since this is the first mention of their occurrence in the Czech Republic, it would be appropriate to study this issue from now to get more results that would be more exact.
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Trematodes of family Opecoelidae in Central Part of Svalbard
OTÁHAL, Ondřej
This study provides results of morphological analyses of material from fishes Myoxocephalus scorpius and Gymnocanthus tricuspis from Svalbard. Adult of Podocotyle atomon were studied using carmine stain and scanning electron microscopy. During fieldtrip on Svalbard experimental infection of intermediate host Amphipoda in the natural environment was documented.
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Manipulation hypothesis: critical review of published works on parasitic invertebrates
TRÁVNÍČKOVÁ, Jana
The manipulation hypothesis has attracted many researchers, and at present it seems to be documented fora wide range of parasites. However, in the last thirty years, numerous parasites have been revealed that, in fact, cannot manipulated with their host morphology, behaviour, and/or habitat preference, unlike conclusions of the previous studies. The major purpose of this study is to test critically the plausibility of the hypothesis about parasitic manipulation, based on metaanalysis of 55 papers concerning four helminth taxa, namely, Acanthocephala, Cestoda, Trematoda, and Nematomorpha.
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Is there a soldier cast in freshwater echinostome trematodes?
ROHÁČOVÁ, Jana
Novel data on the morphology and size of the daughter rediae of the echinostomatid trematode, Echinostoma spiniferum, is provided and their distributions within the first intermediate snail host, Planorbarius corneus, is analysed to test some of the hypotheses of Hechinger et al. (2010) for the existence of social organisation in trematodes.
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Composition and structure of larval trematode communities in model freshwater pulmonate gastropods in eutrophic environments in Central Europe
SOLDÁNOVÁ, Miroslava
This work applies advanced sampling (mark-release-recapture) and comparative approaches addressing the patterns in composition, structure and variability of larval trematode communities in three species of gastropod molluscs (Lymnaea stagnalis, Planorbarius corneus and Radix auricularia) at two nested scales of community organisation in typical Central European eutrophic environments. Hypothesis-testing with the application of null-model analyses, logistic regression modelling and multivariate randomisation techniques, revealed determinants of transmission rates, levels of infection and community structure in freshwater snail hosts in Central Europe and elucidated the mechanisms linking the spatial and temporal environmental variability with the action of complex community assembly rules in freshwater pulmonate snails.
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The occurrence of Fascioloides magna in deers in South Bohemia
VERNEROVÁ, Kateřina
Giant liver fluke Fascioloides magna is the biggest represenative of flukes in the Czech Republic. This originally North American parasite was brought to Europe with wapiti deers in 1960s. Since that time Fascioloides magna has extended the area of its appearance and its host spectrum a lot. The first appearance of this parasite in the Czech Republic was noted for the first time at a fallow deer which was hunted down in Middle Bohemia in 1930. However in the early 1960s the number of positive findings started to increase at hoofed. In the last decade was observed the expansion of areas of appearance of this fluke in South Bohemia. That is why I decided to make examinations to evaluate the recent appearance of F. magna at deer family in the South Bohemia from March 2009 to January 2010. 74 samples of dropping of a deer from three different areas (Českobudějovicko, Třeboňsko and Šumava national park) were collected and examined and only in the sample from Šumava national park were proved the ovulums of F. magna. Then I examined 11 livers of deers which were hunted down in Šumava national park. In all these livers were found macroscopic changes. In all these examined livers was also finding of fluke F. magna in number from 1 to 72. From the reached results follows that the problems of appearance of F. magna is in the Czech Republic still actual and it is necessery to count with the extending area of appearance of this parasite in the future. Edification among hunting community and the use of information from trained people who make the primary examination of animals after hunting down are possible ways to catch up appearance and expansion of this serious parasite at hoofed.
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