National Repository of Grey Literature 31 records found  previous11 - 20nextend  jump to record: Search took 0.01 seconds. 
Molecular biodiversity inventory of the ichthyofauna of the Czech Republic - presentation of the started project
Mendel, Jan ; Halačka, Karel ; Vetešník, Lukáš ; Papoušek, Ivo ; Bartoňová, Eva ; Šanda, R. ; Koníčková, Milena ; Urbánková, Soňa
The study based on international cooperation would like to contribute in a significant way to identification and description of the species diversity of the complete Czech ichthyofauna using a comprehensive approach. The inventory and subsequent cataloguing concentrate on recent native and non-native species of fishes and lampreys living in natural waters of CR. The obtained results are used for inter-continental comparison of all fish species using the "DNA barcode" within the BoLD platform. The final summary evaluation will contribute to updating of the data for monitoring within the system Natura 2000 and will provide vital information and recommendations to the ANCLP CR. The new system of species collections of type specimens designed on the basis of a comprehensive approach and creation of a detailed voucher will mean significant contribution to the Czech museums.
Genetic diversity of grayling (Thymallus thymallus L.) populations in the Czech Republic inferred from microsatellite markers
Papoušek, Ivo ; Halačka, Karel ; Kohout, Jan ; Šlechta, Vlastimil ; Vetešník, Lukáš ; Mendel, Jan
The grayling is among the most valuable fish species in salmonid waters of the Czech Republic. Genetic diversity of twelve grayling populations from all three watersheds of the Czech Republic has been assessed by two multiplex analyses of ten microsatellite loci. Allele frequencies and tests of genotype frequencies for deviation from Hardy-Weinberg equilibrium were carried out. Relationships between respective populations were assessed by Factorial Correspondence Analysis and Principal Coordinate Analysis. Analysis of multilocus microsatellite genotypes from three watersheds of the Czech Republic has shown that significant variability is present in Czech grayling populations. However, this variability has no geographical structure; individuals from all three watersheds form no distinctive groups. It seems that the original genetic structure of Czech grayling populations has already been lost as they have been uniformized by artificial management.
Revitalization of the Morava River vs. business plans
Halačka, Karel ; Mendel, Jan ; Papoušek, Ivo ; Vetešník, Lukáš
The course of the Morava River is an important supranational biocorridor with significant biological potential. This is attested also by results of recent ichthyological surveys. There is a plan of revitalization projects aimed at making migration barriers passable and also at repatriation of indigenous animal species. At the same time, there is a number of business plans focusing on the area, while their realization would severely restrain or even disallow the revitalization efforts. Therefore, a complex biological survey of the whole Morava River course should be performed first, and a detail project of naturalization of the floodplain, including the still existing fragments of original river channel, should be elaborated subsequently. Such project would then constitute a qualified basis for centrally assessed potential business plans.
The latest findings concerning the species diversity of gudgeon of the genera Gobio and Romanogobio in the territory of the Czech Republic and Slovakia
Mendel, Jan ; Lusk, Stanislav ; Lusková, Věra ; Koščo, J. ; Vetešník, Lukáš ; Halačka, Karel
During last 15 years the taxonomy of gudgeon have undergone extensive changes. The findings important for preservation of ichthyofauna of the Czech Republic and Slovakia include confirmation of generic differentiation of the original genus Gobio into two genera Gobio and Romanogobio. On the basis of genetic analyses, the originally accepted uniform structure of the species Gobio gobio was divided into the structures which can be assigned the level of species (G. gobio, G. obtusirostris, G. carpathicus, Gobio sp.). The original R. albipinnatus can be divided into the species R. vladykovi and R. belingi. The original species R. kesslerii can be divided into R. banaticus and apparently also Romanogobio sp. With regard to newly acquired knowledge it is necessary to revise the system of efficient preservation of the biodiversity found in the above mentioned taxa. The areas of sympatric occurrence of some species were localized and hybridization within both the genera was demonstrated.
Ploidy and sexual status of the "Carassius auratus" complex in the waters of the Czech Republic
Lusková, Věra ; Lusk, Stanislav ; Halačka, Karel ; Vetešník, Lukáš ; Papoušek, Ivo
The "Carassius auratus" complex, non-indigenous in the Czech Republic, comprises several forms: C. a. auratus (decorative form), C. a. gibelio (predominant), and C. a. langsdorfii (Japanese form). C. a. gibelio is considered a "non-indigenous invasive species". Around 1975, the form invaded the waters of the Czech Republic from the Danube drainage area. The first invasive individuals were triploid females reproducing gynogenetically. The first males occurred in the Dyje River drainage area after 1990 and began transforming to a mixed type, both the sexual and ploidy status of C. a. gibelio populations changing. At present, the overall percentage representation of males in C. a. gibelio populations varies around 30 %, most of them being diploids, triploids occurring only occasionally. A larger part (60 %) of the females, which still predominate in the population, are triploids, the rest being diploids. Tetraploid individuals of both sexes occur quite singly.
Population and genetic structure of trout (Salmo trutta) and grayling (Thymallus thymallus) as a basis for a successful fishery management
Halačka, Karel ; Papoušek, Ivo ; Kohout, Jan ; Vetešník, Lukáš ; Lusk, Stanislav ; Mendel, Jan ; Šlechta, Vlastimil
The aim of the study is to contribute to knowledge about population dynamics of our salmonids. The study concentrated particularly on the genetic diversity of Salmo trutta and Thymallus thymallus populations, and also on selected morphological characters. Genetic analyses of the mitochondrial DNA have shown an existence of an extreme uniformity of populations in all three sea-drainage areas. Due to anthropogenic interventions, structure local subpopulations adapted to given local subpopulations, resulting from the natural diversification spanning thousands of years, has been disrupted. All other individuals carried a uniform (Atlantic) haplotype. A comparison study dealing with structure and dynamics of epidermis in S. trutta, O. mykiss, S. fontinalis and T. thymallus has shown significant differences particularly in fraction of the secretory cells. Lower proportion of the secretory cells in T. thymallus could be related to its sensitivity to molds in the post-spawning period.
Secundary trout zones and occurrence of grayling (Thymallus thymallus) in the territory of the Czech Republic
Halačka, Karel ; Lusk, Stanislav ; Vetešník, Lukáš
In this paper, the relationship between emergence of secondary trout zones below dams, and occurence of the grayling in the waters of the Czech Republic, is studied. The grayling was mentioned as a potentially perspective fish for our waters. This was confirmed by colossal growth of its catches in 1970s and 1980s. The space formed by creation of the secondary trout zones below series of dams, which were built at that time, was very significant for this growth. However, at the turn of the century, a breakpoint was observed, and the numbers of catches decreased to the level of the 1950s. It can be stated that these locaties appear very suitable for this species under specific conditions. However it is necessary to monitor the general dynamics of this biotope, in order to possibly establish an optimal regime fit for present organisms and therefore to form a stable equilibrium.
Large-scale rehabilitation in the alluvial area along the lower reaches of the Dyje River
Lusk, Stanislav ; Pražák, O. ; Lusková, Věra ; Halačka, Karel ; Vetešník, Lukáš
The Dyje River between Lednice and Bulhary was straightened, canalised, and provided with levees. Most of the alluvial area near Podivin was transformed to arable land. Due to elimination of floods, save for exceptions, areas denoted as wetlands and reed beds were qute dry for most of the year. As a result, the native fish communities typical of alluvial habitats gradually vanished from their habitats. In recent years, some 470 hectares on the left bank of the Dyje River, owned by a single private person, were transformed into a deer sanctuary. In the past two years, the arable land in that area has been gradually turned into meadows and a floodplain forest, together with restoring and enlarging the area of permanently waterlogged parts denoted as wetlands. As a result, the conditions permitting permanent occurrence of fish have been significantly improved and for a purposeful restoration of their fish communities in which native species predominate (the Carassius-Misgurnus type).
Molecular biological analyses of Sand gudgeon (Romanogobio kesslerii) in the waters of the Czech Republic and Slovakia
Mendel, Jan ; Lusk, Stanislav ; Lusková, Věra ; Koščo, J. ; Papoušek, Ivo ; Halačka, Karel ; Vetešník, Lukáš
Kessler's gudgeon belongs to critically endangered species protected by both national and European legislation. We present the first findings concerning the genetic diversity of 5 R. kesslerii populations from the Czech and Slovak rivers. On the basis of sequencing of the control region, as well as of the first intron of the S7 r-protein, 30 specimens were analysed. Altogether nine haplotypes were identified. Analyses of mtDNA showed the existence of two groups differing by 6.2%. The first group included the specimens from the rivers Bečva and Ipel and the second group included the specimens from the rivers Topl’á, Laborec and Morava. The inter-population diversity was 0.4% within the first group and it ranged from 0.5% to 1.0% within the second group. The combination of the methods of sequencing of parts of mtDNA and nDNA and allozyme analysis revealed the presence of hybrids of G. gobio and R. kesslerii in the Morava and Ipel’ rivers.

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