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Potrava dravých ryb vodárenských nádrží povodí Moravy
Mikl, Libor ; Adámek, Zdeněk ; Šlapanský, Luděk ; Všetičková, Lucie ; Jurajda, Pavel
Biomanipulace jsou považovány za jeden ze základních pilířů, kterými je možné ovlivnit jakost vod na vodárenských nádržích. Pro posouzení možností a účinnosti biomanipulačních opatření na vodárenských nádržích v povodí Moravy (Bojkovice, Ludkovice, Landštejn, Nová Říše a Hubenov) proběhly během jarních a letních měsíců v letech 2016 a 2017 kontrolní odlovy ryb (Jurajda et al. 2018). Ryby byly odlovovány s použitím elektrického agregátu a tenatních sítí. Na potravní analýzu bylo celkem odloveno 922 jedinců (dále ind.) dravých ryb: štika obecná (39 ind.), bolen dravý (24 ind.), okoun říční (805 ind.), candát obecný (43 ind.) a sumec velký (11 ind.).\nRybí složka v potravě dravých ryb studovaných vodárenských nádrží, tvořila celkem 75 % hmotnostního zastoupení z celkově přijaté potravy a dominovaly v ní především kaprovité ryby s 41 % hmotnostním zastoupením (plotice 15 %, perlín 12 %, cejn 8 %, ouklej 3 % a blíže neidentifikovatelné kaprovité ryby 2 %) a okounovité ryby s 20 % (okoun 15 %, candát 2 %, ježdík 1 % a blíže neidentifikovatelné okounovité ryby 1 %). Natrávené zbytky ryb, které nebylo možno zařadit do žádné vyšší taxonomické skupiny, tvořily 12 %. Druhou nejpočetnější složku potravy tvořili bezobratlí (24 %). Nezanedbatelnou část kořisti predátorů tvořily i samotné dravé druhy ryb 23 % (okoun 15 %, štika 4 %, candát 3 %, blíže neidentifikovatelné okounovité ryby 1 %). Kanibalismus se na složení potravy dravých druhů ryb podílel celkem 11 %, u okouna tvořil 15 %, u štiky a candáta shodně 13 %, zatímco u bolena a sumce nebyl zaznamenán.\nVýsledky potravních analýz spolu s monitoringem rybích společenstev studovaných nádrží, při němž byl zjištěn poměrně vysoký poměr dravých ku nedravým rybám (Jurajda et al. 2018) naznačují, že za současného stavu biomasy dravých ryb a vstupu nutrientů, mohou biomanipulační opatření sloužit maximálně jako prostředek k zakonzervování současného stavu jakosti vod na vodárenských nádržích, nikoliv jako opatření, které by mohlo významněji přispět ke zlepšení kvality surové vody.
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Hejnové chování jako odezva na změny prostředí, přehledová studie
JAKŠ, Jiří
The aim of my bachelor thesis was to create a review about effect of some parameters on shoal of fish. In my thesis may be found information about effects of different parameters on shoal of freshwater, marine and aquarium fish species. Review describes several parameters that effect fish in several ways and it is also contains a lot of information about shoal behaviour in general. Review gradually passes from general definition of shoal, creation of shoal, types of shoal, advantages and disadvantiges of shoal, communication and recognizing of fish inside the shoal, to enumeration of parameters that effect fish both positively and negatively. In conclusion may be found possibilities of modeling fish and their behaviour on two model examples. Information come from Czech literature, but also from foreign literature, which makes my thesis more creative and objective. Shoal behaviour is still relatively unexplored topic and many questions still remain unanswered. Exploring and assesing of shoal behaviour is relatively complicated, therefore the answers are only author´s opinions and several experiments results. Although there are speculations about this topic, many authors and experiments have similar opinion. My bachelor thesis may appreciate those, who want to know more about the shoal behaviour. In future it is necessary to realize more research about shoal behaviour and fish modeling because of its use and and less public awareness.
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Taxidermal Mounts of the Reptiles, Small Mammals and Fishes
Kubátová, Claudie ; Řezníček, Jan (advisor) ; Poláchová, Tereza (referee)
1 ABSTRACT The thesis is conceived as detailed guide to create a dermoplastic models for teachers of natural history and biology. The first part focuses on the actual field of taxidermy and its methods. It includes some possible methods leading to the making of dermoplastic models of mammals, reptiles and fishes. The second part describes the created models of mammals, reptiles and fishes. This section also contains the characteristics of individual species and recent research from specialized foreign literature.
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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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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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Phylogeny and biogeography of Neotropical and African riverine cichlids: multilocus phylogenetic methods in the evolutionary studies
Musilová, Zuzana ; Novák, Jindřich (advisor) ; Bryja, Josef (referee) ; Reichard, Martin (referee)
Summary: The thesis comprises from the introduction and five main parts: three of them are published papers, the rest two are manuscripts prepared for submitting to the scientific journals. The first two are published phylogenetic studies of the cichlasomatine cichlids based on (1) molecular characters, and (2) both morphological and molecular data with the description of a new genus Andinoacara. The third (3) is the already published description of the new species Andinoacara stalsbergi from Peru combining both morphological and phylogenetic approaches and including the detailed phylogeny of the genus Andinoacara. The next unpublished manuscript (4) is the more detailed comprehensive phylogeography of the two non-relative genera (including Andinoacaras) of the trans-Andean cichlids. Including all valid species from the majority of their distribution areas it was reconstructed the ancestral area of both genera in the Choco region, Colombia, and revealed the directions of their distribution spreading. The last (5) unpublished manuscript is the phylogeographical study of the cichlid genus Serranochromis from the headwaters of the totally unknown Central Angola. It showed several evidences of the faunal exchange among the adjacent river systems. Lastly, the thesis is supplemented by several appendices...
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On the origin of words (Freshwater Fish Labelling Etymology in the Czech Republic and European English-speaking countries)
Novák, Lukáš ; Řezníček, Jan (advisor) ; Rajchlová, Štěpánka (referee)
The thesis doesn't have the tendency or ambition to reach the particular conclusion or final solution (which would be at least as debatable as the construction that it is based on). But it should bring different approach and focus on selected animal genus (our distant ancestors), accepting them as a contemporary cultural, economical and culinary interest. Insight trough the prism of tendency, specifics and unwritten rules of linguistics, under the thumb of cultural representativneness and its identification. The contact of two distinc worlds, antithesises. The silent and peaceful world of fishes, that has retained the objectified prism of lucent wall under the water level, which singularises it from antropocentric world of "those", who think to stand on the top of imaginary pyramid. The work is divided in three parts: Introductory principles, etymological research and addendum, which interprets fish from the art, astronomy, folklore, and booklore point of view.
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Life around the water and in the water, five environmental programs for kindergarten
KREJČOVÁ, Hana
Krejčová Hana 2014: Life around the water and in the water, five environmental programs for kindergarten. Bachelor thesis. Faculty of Education, University of South Bohemia in České Budějovice, 63 pp. My bachelor thesis contains practical elaboration of five environmental programs for kindergartens. Main theme is life of animal around the water and in the water. I have chosen these themes: "Snails", "Insects", "Fishes", "Frogs", "Lizards and Snakes." Bachelor thesis contains beside practical part also theoretical part focused on pedagogy and natural science. Theoretical part is way-out for practical elaboration of all activities included in the submitted programs. My bachelor thesis also contains a discussion about suitability of form and content of the suggested environmental programs according to experiences of kindergarten teachers. Respondents have been asked by on-line questionnaire.
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Changes of biochemical parameters in fish after nitrite exposure
PODLESNÝ, Martin
The aim of this thesis was to assess the effects of long-term nitrite exposure on mortality, growth rate and blood biochemistry in rainbow trout (Oncorhynchus mykiss). Furthermore, acute toxicity tests with nitrite were performed on rainbow trout (Oncorhynchus mykiss) and sheatfish (Silurus glanis). The theoretical part focuses on aquatic toxicology including toxicity evaluation of substances and preparations for water organisms. Detailed information on nitrite are summarized there, namely information on nitrite occurrence and sources in aquatic environment and the mechanism of their uptake and toxic influence on fish including factors influencing their toxicity. The practical part consists of methodology and results of acute toxicity tests on rainbow trout and sheatfish and sub-chronic test on rainbow trout. According to the acute toxicity tests results, 96hLC50 values were estimated at 11.2 mg.l-1 NO2- for rainbow trout and 15.3 mg.l-1 NO2- for sheatfish. Sub-chronic exposure of rainbow trout to nitrite concentrations ranging from 0.01 to 3.0 mg.l-1 lasting 28 days caused an increase of glucose concentration and a decrease of potassium concentration in the blood plasma among all experimental fish compared to control. Elevated nitrite levels were found in the plasma of the fish exposed to concentrations of 0.6 mg.l-1 NO2- and greater. The plasma nitrite levels did not reach those applied in any experimental group in the present study. At highest nitrite concentration (3.0 mg.l-1 NO2-), 42 % growth inhibition and 65 % mortality among fish was noticed. On the basis of growth rate inhibition data, the values of NOEC and LOEC were estimated at 0.01 mg.l-1 and 0.2 mg.l-1 NO2-, respectively.
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