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Hybridisation of cyprinid fishes in the Czech Republic: genetic and morphometric analysis of the subfamily Leuciscinae
Kaufman, Vít ; Musilová, Zuzana (advisor) ; Choleva, Lukáš (referee)
Hybridization is a process when two interspecific individuals mate and spawn. When backcrossing it often goes hand in hand with admixing unrelated genome into the genome of a species. Nowadays it is well established that hybridization is not as uncommon as it was believed. Especially in vertebrates fish are quite common in such phenomena. In Leuciscids, the family of order Cypriniformes is relatively frequent. It is a rife family in the European freshwater systems. Factors that contribute to such frequent hybridization are extraneous fertilization, sympatric occurrence, competition for spawning grounds, and other ecophysiological traits. It was known since the second half of 20th century that this is an ongoing phenomenon in many species of this family. Previous research was focused mainly on morphological traits. The relative pinnacle of such research was based on allozymic analysis. The goal of our project was to evaluate the level of hybridization in the main water bodies of the Czech Republic with the main focus on the detection of involved hybrid species, the level of such hybridization, and the phenotypic characterization of hybrid individuals. For that reason, it was sampled over 400 specimens giving a dataset of 381 individuals. Tissue samples were sampled for DNA isolation and each of the...
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Fish and fish products in the sector public catering
KUNÁGLOVÁ, Jana
The bachelor thesis is focused on fishes and fish products in the catering sector. The content of the theoretical section is general information about fishes and their subsequent processing into the fish products. The practical part is focused on the public catering sector in the Czech Republic, where the inclusion of fishes in the menus of restaurants and canteens, with an orientation on fish species, method of preparation, average portion weight, price and nutritional value of fishes offered in the public catering sector.
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Fish and fish-like vertebrates in educational system of primary and high schools
Kasíková, Tereza ; Hanel, Lubomír (advisor) ; Andreska, Jan (referee)
Title Fish and fish-like vertebrates in education system of primary and high schools. Abstract Based on analysis of schoolbooks for primary and secondary schools (11 analysed schoolbooks) and for grammar schools and high schools (5 analysed schoolbooks) I compile frequency (percent occurrence) of fish and fish-like vertebrates nomenclature in my diploma thesis. On this base I prepared the table unifying Czech and scientific nomenclature of all analysed schoolbooks. Whereupon this unifying I created the recommended list of presently valid Czech and scientific terms of fish and fish-like vertebrates for primary and high schools. Furthermore, based on schoolbooks analyses, I compile didactic availability of particular chapters dedicated to fish and fish- like vertebrates. Using of didactic test I surveyed the student`s knowledge at the grammar school. To extend the subject matter of fish and fish-like vertebrates I created teaching presentation "Man and Fish" for basic schools and high schools. I prepared excursions proposal for students where I described in a detail where to go to see main representatives of fish and fish-like vertebrates all around the Czech Republic.
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Fish Herpesviruses
Čečetka, Petr ; Forstová, Jitka (advisor) ; Kuthan, Martin (referee)
Herpetic viruses that attack fish are ones of the most widespread virus pathogens, threatening modern day fish population not only in the wild but also those that are farmed. There are many types of the pathogen, from the ones those do not cause severe diseases to those that are extremly dangerous, spread without any control and caused vast losses in commercial farming and in wild populations. Most of the viruses exhibit increased sensitivity on heat and stress factors, which are the most common reasons of the repeating outbreak of disease. To the best described fis herpesvirus viruses attacking fresh water fishes belong. Nowadays more and more herpetic viruses which attack mainly salt water fis are beeing discovered. Powered by TCPDF (www.tcpdf.org)
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Cone mosaic in the retina of ray-finned fishes and its function for vision
Konvičková, Zuzana ; Musilová, Zuzana (advisor) ; Němec, Pavel (referee)
Ray-finned fishes comprise more than half of the vertebrate diversity, and they developed many unique strategies and adaptations to inhabit miscellaneous water environments. This thesis is dedicated to vision, which is an indispensable sense for most fishes. Special focus is laid on photoreceptor morphology and their arrangement in a two-dimensional pattern - cone mosaic. There are three morphological types of photoreceptors commonly found in ray-finned fishes - rods, single cones, and double cones. Triple and quadruple cones that have never been observed in any other vertebrate group sometimes occur too. In this thesis, I discuss the structure and function of individual photoreceptors. While rods are randomly distributed across the retina, cones often form a regular mosaic. Several basic mosaic types can be distinguished according to the position of double cones. Row and square mosaics are the most prevalent. Basic patterns can be further modified in certain fish species. In this thesis, I describe basic patterns, I focus on mosaic development, and I investigate the reasons for regular photoreceptor arrangement. The type of mosaic partly reflects phylogeny, but it is also strongly influenced by the environment and life strategy of the fish. Active fishes inhabiting bright environments are likely...
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The impact of eutrophication on fish in running waters
Jeníšová, Karolína ; Horká, Petra (advisor) ; Frouzová, Jaroslava (referee)
Eutrophication belongs among be the most serious factors threatening freshwater ecosystems. Eutrophication is a result of excessive nutrient loading which comes mostly from both the point-source and diffuse pollution and agriculture, increased sediment loading from soil erosion, but also due to a presence of various types of impoundments, which, particularly in some areas, represent a significat part of nutrient supply. Although the effect of eutrophication on freshwater fish communities has been thoroughly studied in standing waters, very little attention has been paid to running water ecosystems. Among the processes with the most pronounced impacts on fish communities are increased phytoplankton growth and loss of macrophytes, low oxygen levels or anoxia, occurrence of toxic forms of nitrit and ammonia and elevated turbidity and subsequent light reduction. Whilst the diversity of fish communities is not usually affected, changes in structure of fish communities and decreased ecological quality has been detected with the increasing level of eutrophication. The most sensitive fishes are salmonids as they have high oxygen demands and are very sensitive to a toxic forms of nitrogen. Moreover they are visual predators highly affected by the increased turbidity of water environment. Percids are mainly...
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Taxidermal and Skeletal Mounts of Fishes
Hájková, Magdaléna ; Řezníček, Jan (advisor) ; Hanel, Lubomír (referee)
This thesis is conceived as a detailed guide to the creation of didactic aids, namely the creation of dermoplastic preparations and fish skeleton for teachers of natural science and biology at various levels of schools. In this work we describe individual prepared fish species. The diploma thesis works to verify the diploma thesis Martin Chlad, who recently developer a detailed methodology for body preparation of the whole fish. The result of the practical part of the thesis are fish models that serve to extend the collections of the Department of Biology and Ecological Studies and to extend the collections of the Biological Cabinet to my current work place at elementary school in Prague 9.
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