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Angl. resumé

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Fish meat compared with other meats t have a very specific composition, which is good for the human. On the other hand, the composition of the fish meat is excellent medium for the growth of undesirable microflora, which can lead to foodborne illness, and rarely death of a person. In this work were examined these microorganisms: Total plate count, coliform organisms, E. coli, genera Salmonella, Vibrio and Listeria. As as a samples were used three species for our most consumed fish. As a sample was used three samples of fish meat from three different shops and for the samples was used two storage temperatures. Other were four samples of smoked fish. The obtained results were compared, with the now invalid, Decree No. 132/2004 Coll. and Commision regulation (ES) No. 2073/2005. Based on the obtained results it can be stated that there was statistically significant difference in the total nummer of microorganisms, coliform organisms and E. coli between stores. It also was not statistically significant difference in the total nummer of microorganisms, coliform organisms and E. coli selected storage temperatures between 4 °C and 8 °C. The highest total nummer of microorganisms in smoked fish was detected in a sample of sprat in the amout of 6,67 log CFUg-1. The highest nummer of coliform organisms in the sample was also sprat in the amount of 5,02 log CFUg-1. E. coli was detected in smoked fish with only one sample, the sample smoked bream in an amount of 2,03 log CFUg-1. Composition of the microflora in fish muscle is influenced by many factors. Every organism requires different conditions for their growth. These conditions must be known to the exclusion of undesirable microorganisms from food .

In recent years there has been a significant decrease in abundance and species diversity of migrating fish. A significant decrease was recorded especially in diadromous fish species such as Atlantic salmon (Salmo salar) and eel (Anquilla anquilla). A significant population decline was also observed in potamodromous abundant fish species. Transverse barrier which prevents fish migration in rivers and impaired water quality are considered as the main causes of this situation. At present there is being improved a surface water quality, habitat rehabilitation and restoration of the possibility of free migration of aquatic animals. Design and construction of fish ladders are the most important factors to improve conditions of the fish migration. Closely related to this is a migration permeability testing of these fish ladders while the biological function and the activity of a single technical solution is evaluated. A non-invasive automatic monitoring method using a bioscanner Riverwatcher was selected to assess the functionality of fish passage on the river Ohře in Kynšperk nad Ohří. Bio scanner was installed at the end of the track of fish passage. Riverwatcher camera system, a product of Vaki Aquaculture Systems Ltd., was used in the Czech Republic for the very first time. Direct catches of fish samples in the river using an electric unit (section under fishway) were also used for the data collection. Size and species selectivity was tested at the fish ladder. The influence of external factors affecting the course of migration, such as flow rate, water temperature and light, was monitored at the same time.

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This master thesis is dedicated to the determination of concentration of selenium and mercury in seafood. The theoretical part is devoted to the selenium characteristics, toxicity and occurrence of the biochemical functions of selenium and the relation of selenium and mercury in fish. The practical part deals with the determination of selenium and mercury in fourteen species of fish that have been purchased fresh or vacuumed in chains store in the Czech Republic. Analysis of the selenium content was performed by atomic absorption spectrometry with electrothermal atomization. Determination of the total mercury content was performed with using atomic absorption spektrometer AMA 254. Results of total mercury contents were compared with legislative limits as per Commission Regulation (EC) No. 629/2008. Selenium Health Benefit Values Se-HBV were calculated.

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.