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Occurence and diversity of amphibian trypanosomes
Poloprutská, Klára ; Votýpka, Jan (advisor) ; Brzoňová, Jana (referee)
The genus Trypanosoma represents well-known flagellates of order Trypanosomatida and class Kinetoplastea, which includes over 500 described species parasitizing on all classes of vertebrates. However, the best known and economically and medically most important are mammalian trypanosomes, especially human ones, which cause serious diseases in the world: sleeping sickness in Africa and Chagas disease in Latin America. But trypanosomes may also be found in blood of birds, reptiles, fish and amphibians. And exactly on trypanosomes of amphibians, whose diversity is surprisingly vast, is this thesis focused. However, many studies concentrate only on morphological description, which may not be the best in order to determine species, which may lead to distortion of information e.g. about species' life cycle, prevalence or host specificity. This thesis points to some ambiguities, but also to some more reliable experimental or in some cases molecular evidence dealing with individual aspects of life of trypanosome of amphibians. It also summarizes representatives of aquatic and terrestrial invertebrate vectors of trypanosomes, among which leeches are considered to be the dominant vector in aquatic environment. Furthermore, some species of phlebotomes, mosquitoes and genus Corethrella are known to be...
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Cellular and molecular basis of a skin regeneration in amphibians and mammals
Hybešová, Michaela ; Krylov, Vladimír (advisor) ; Jendelová, Pavla (referee)
Wound healing of skin in mammals and its regeneration in Amphibians are crucial biomedicine topics in the last few decades. The most important aspect in humans is the scrarring proccess and the effort to substitute it with the regeneration producing functional and differentiated tissues. To modulate the formation of scar it is neccessary to compare both proccesses. The core animal model is axolotl (Caudata) where regeneration takes place during whole lifespam. On the other hand, in frogs (Anurans) this phenomenon is restricted up to metamorphosis. After metamorphosis, the immune system of Anurans is similar if compared to mammals. Similarly, the transition from early embryonic development in mammals, where the fetus was able to completely regenerate damaged tissue to an adult type of healing, goes hand-in-hand with the development of the immune system and structural differentiation of damaged tissue. Thus, the inflammatory cells and their regulation, the formation of ECM, which includes fibroblast proliferation, and the production of appropriate cytokines are key factors that distinguish the process of healing with and without scarring.
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Hunting mechanism and visual perception of prey in amphibians
Košinárová, Lucie ; Frýdlová, Petra (advisor) ; Černý, Rudolf (referee)
Visual perception holds the dominant position among other senses in amphibians. It provides vital information about any potential prey or predators in the surrounding area. Any information, gained through optical sensors, is then directly evaluated in brain, activating different behavioral reactions: prey catching or predator avoidance behaviour. Decision is based on individual parameters of stimuli. In case of identifying a prey stimulus an innate behavior pattern is activated. There are many prey catching strategies in amphibians. Their selecting may vary due to many aspects including food preferences, mechanical constraints or a phylogenetic position of the species. Habitat may also have an influence over hunting strategy or even morphological characters of species, mostly regarding their oral system. Tongue plays an important role in almost every prey catching movement in terrestrial and also in some aquatic amphibians. There are different types of tongue elongation in amphibians that are divided into several categories, which can affect the hunting strategy for each species. Apart from creating a summary about visual perception and hunting mechanisms, this thesis includes a mapping of different types of tongue elongation on a phylogenetic tree of amphibians. The main goal of this task is to find a...
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The response of Marsh Frog (\kur{Pelophylax ridibundus}) to the presence of alien predators
KROUFKOVÁ, Michaela
This study focuses on the antipredator strategies of amphibian larvae in relation to some of their predators. Namely, the relationship between the larvae of the marsh frog (Pelophylax ridibundus) and the invasive species of the fish, the topmouth gudgeon (Pseudorasbora parva). Latter part of the experiment involves investigation into the relationship between another non-native species, the three-spined stickleback (Gasterosteus aculeatus). Both are non-native species of small fishes. The topmouth gudgeon was introduced unintentionally in the 1980s from Hungary. It is listed on the Black List of the Czech Republic and it is on the list of invasive non-native species of the EU Regulation (1143/2014), (Kuřátko, 1998; Poláková et al., 2016). The three-spined stickleback was brought into our territory from America. It was probably released into local ponds by Czech aquarists at the beginning of the 20th century. It is a species that is not listed on the Black List of the Czech Republic, but its negative impact on fish fry has been previously documented (Poláková et al., 2016). Both species have been known for a negative impact on the biological diversity of our fauna, but the influence of these predators on our amphibians has not so far been documented. The experimental part investigates the damage of tadpoles caused by these non-native fishes and the defensive strategy of the tadpoles. The tadpoles were provided with a hiding place as one of the possible escape strategies against the predator.
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Diverzita obojživelníků (Amphibia) a jejich antropogenní ovlivnění v národním parku Podyjí
Bohuslavová, Markéta
The thesis focuses on amphibian species diversity in the National Park Podyjí. There were chosen four areas with various anthropogenic loads, on which monitoring was being regularly performed. Those areas were specifically ponds; Čížovský, Dehťák, under Lesná and a swimming hole called Na Pyramidě. To achieve a numerical representation along with a representation of species, invasive and non-invasive monitoring methods were used. During the research, eight different species were detected, even though there were eleven of them founded in the past. Among the most abundant species is the Common toad, the Agile frog, the Common frog, the Northern crested newt and the Smooth newt. Surprisingly, the presence and successful reproduction of northern crested newts was proved in the pond under Lesná, on the other hand, there were no signs of moor frogs or any other common water frogs. The collected data were afterwards used to calculate synecological characteristics (dominance, species diversity, equitability and the Jaccard similarity coefficient), while the achieved results were compared with the other authors and evaluated in terms of anthropogenic influence. The amphibians in the national park are threatened by a high fish stock and the absence of littoral vegetation. Recommended management within the areas would be to catch and then deploy the appropriate species of fish, as the case may be, build barriers and create the littoral zone.
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Studie revitalizace mokřadního biotopu v k.ú. Šanov
Doleželová, Zuzana
The thesis deals with proposal of suitable revitalizing measures in local biocentre in cadastral area Šanov (district Znojmo). The proposal aims to create a near-natural habitat, which would provide good conditions for the occurrence of wetland plants and animals and contribute to the increase in biodiversity in the area and also became functional element in terms of water retention in the landscape. The proposal is the trenched non-flow pools with fluctuating water level during the year and their vegetally connects. The thesis provides information about possible sources of funding restoration measures.
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Amphibians - the Meaning for Men and their Use in School Education
Vajnar, Tomáš ; Hanel, Lubomír (advisor) ; Andreska, Jan (referee)
This work contains a research on the class amphibia and evaluate the relationship between man and amphibians (morphology, physiology, biology, etology, bioindiation, threat and conservation of amphibians, myths, toxikology etc.). Amphibians are analyzed as a model group with respect of using them in educational praxis (model group of animals in education of biology, zoology, ecology, etology, nature protection, literature etc.). Exotic species are choosed as examples, which are best for care in schools. Here are made also manuals for breeding of selected less demanding species in aquarium or aqua-terrarium conditions and for observing their life histories.
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Summary of the upperpalaeozoic amphibians of Czech republic
Vala, Vladimír ; Mazuch, Martin (advisor) ; Zajíc, Jaroslav (referee)
The topic of my thesis is an overview of Late Paleozoic amphibians in the Czech Republic. Stegocephalians are ancient amphibians, which evolved in the Upper Devonian and were most prevalent during the Carboniferous and Permian, some species survived into the Cretaceous. They are highlighted in the amphibian system and their anatomy is briefly described. We divide them into two large groups - Labyrinthodontia and Lepospondyli who are different in many ways, which are briefly described in my work. Stegocephalian findings are limited only to sedimentation areas of basins and furrows, in the Czech Republic to the West Bohemian basins, Piedmont basins and Boskovická furrow. In the very list of species I have tried to describe the species representing most of the known groups. Information of some species are sketchy because there are few found fossil remains, findings are in most cases incomplete, and many of these species are still the subject of research.
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