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Parental behaviour and its relationship to social and reproductive system in voles \kur{(Microtus, Arvicolinae)}
ELIÁŠOVÁ, Michaela
I examined parental behaviour of three vole species, the brandt{\crq}s vole (Microtus brandti), the common vole (M. arvalis) and the levant vole (M. guentheri) in laboratory conditions. Monogamous and highly social Brandt{\crq}s voles displayed high levels of parental and paternal care. However, mostly promiscuous and solitary common voles also exhibited an intensive parental care. In contrast, polygynous and social levant voles displayed very low levels of parental care. Males of both latter species engaged in parental activities but spent less time in contact with pups then females. These findings suggest that intensive parental care may be connected rather with the high growth rate a slower postnatal development of the species than with social or reproductive system.
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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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Růst krátkých trhlin z vrubů ve dvoufázové austenitcko-feritické oceli
Kotecký, Ondřej ; Degallaix, S. ; Polák, Jaroslav
The effect of microstructure and stress gradient in a two-phase austenitic-ferritic steel in specimens with confined plasticity is studied. Direct optical observations and potential drop technique calibrated via the finite element method are used to measure the surface crack size and its depth and to determine the surface crack growth. The effect of stress and strain gradients on the crack propagation kinetics and crack shape is evaluated and dicussed.
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Individual growth and weight condition of the common carp (Cyprinus carpio m. domestica) in the Nové Mlýny Reservoir (preliminary results)
Habán, V. ; Prokeš, Miroslav ; Baruš, Vlastimil ; Mareš, J.
Individual tagging of the carp (C. carpio f. domestica) 2-year stockfish (K2) was initiated in 2001. In total, 10 thousands specimens were so far tagged with the anchor plastic tags and released into the Nové Mlýny Reservoir on the River Dyje in 2001-2005. According to the 36 registered recaptures (in 2004), the carp reached in the third year of life after 11-12 months exposition in the reservoir (D 316-317, mean 345.3), a body mass of 1500-3900 g (mean = 2264.4+-802.6 g) and a total length of 420-530 mm (mean = 464+-33 mm). These values reveal high trophic sources existing in the Nové Mlýny Reservoir being filled in 1988. When compared with similar data from fishponds of the Czech and Slovak Republics, the growth rate observed showed to be similar or even higher.
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Growth comparison of the (1+) juvenile sterlet (Acipenser ruthenus) by using experimental and commercial diet
Baránek, V. ; Prokeš, Miroslav ; Baruš, Vlastimil ; Peňáz, Milan ; Cileček, M. ; Mareš, J. ; Jirásek, J. ; Spurný, P.
The aim of this experiment was to check the growth rate of the (1+) juvenile sterlet. The experiment was proceeded during the 42-days period (25 July - 4 September 2005) in the hatchery of the Pohořelice Pond Fisheries. The fish were kept in four flow through tanks. In total, 45 individuals were stocked in each tank. Fish were fed by experimental (44/12) and commercial diet (Pro Aqua Brutfutter 57/15, Skretting) in two repetitions. Our experiment confirmed very good growth ability of the juvenile sterlet, together with low FCR parameter. Sterlet may be considered as an appropriate fish for intensive aquaculture and also, as a native species of the Czech Republic for stocking into Czech running waters.
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Czech Republic gross domestic product analysis
Kabelková, Renata ; Pavelka, Tomáš (advisor) ; Džbánková, Zuzana (referee)
The topic of my essay is the analysis of the gross domestic product of the Czech Republic in years 1999-2009. It consists of methodological and analytic parts. The methodological part describes basic terms needed to understand given issues. The analytic part details GDP of the Czech Republic in the monitored period. Analysis is made by comparisons between years and between quarters in constant prices of the previous year. Causes of development are described in detail including their positive and negative impact on the macroeconomic indicator. At the end of the paper there is an overall assesment of the GDP development and major events that affected it.
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