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Intenzivní chov okounka pstruhového (Micropterus salmoides) v RAS s různým světelným režimem
BOŇKO, Dominik
Largemouth bass (Micropterus salmoides) is one of the species of fish that don´t have a significant position among the species of fish breeded in Czech Republic. However the trend of building aquaculture recirculation systems with warm water comes to the fore. Breeding in these conditions opens up the possibility of introducing new kinds of thermophilic fish species. Largemouth bass definitely belongs to this group. The general factors of successful breeding of largemouth bass are the temperature and purity of the water, the suitable-composed diet and the correct stocking density. This work studies another factor that not only participates in the success of the breeding, but also has influence on the energy expenses of the aquaculture system. It is the effect of photoperiod during breeding. Five experimental groups with three repetitions were created according to the time of lighting (8, 12, 16, 20 and 24 hours of light a day). The experiment lasted 16 weeks. The average water temperature was 24,6 °C. The initial stocking density for all tanks was 20.6 kg . m-3. Fish had an initial average weight of 32.6 +- 2.1 grams. The feed ration was set up at 1% of biomass per day. As a diet were used a floating dry pellets Skretting R-2 Europa 15 F of 2 mm. The feed contained 55 % of protein and 16 % of fat. Fish were fed manually by hand. All groups showed high survival during the experiment (99.4 - 100 %). The best results were achieved by a group of 8 hours with the highest feed conversion (FCR = 0.94 +- 0.06) and the highest growth rate (SWGR = 0.6 +- 0.04 % . day-1). The average individual fish weight of the 8 hour group at the end of the experiment was 64.07 +- 2.82 g. On the other hand, group of 12 hours was the worst with the lowest average individual weight (W= 57.51 +- 1.51 g), growth rate (SWGR = 0.49 +- 0.04 % . day-1) and the lowest feed conversion (FCR = 1.16 +- 0.08). These two groups were significantly different in most production indicators. The pervisceral fat index grew with biomass. The longer the photoperiod, the higher the plasma and ammonia content of lactate. In contrast, glucose content decreased. A longer photoperiod also influenced the higher production of antioxidants.
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Selected aspects of intensively cultured European whitefish (Coregonus maraena, Bloch) and peled (Coregonus peled, Gmelin)
ŠEBESTA, Roman
Maraena whitefish and peled are considered to be economically important fish species. This Ph.D. thesis deals with testing of selected aspects which show potential for improvement of quality and effectivity of larvae and juveniles of both fish species in recirculating aquaculture systems. The whole Ph.D. thesis includes 9 chapters described in 125 pages. In chapters 2-8, there are described the individual factors which can influence quality of intensive rearing of mentioned fish species. The effect of light intensity and tank wall colour on growth and survival of peled larvae is tested in chapter 2. The effect of different temperature on growth and survival of maraena whitefish larvae is presented in chapter 3. The effect of various stocking density on growth and survival of maraena whitefish larvae is given in chapter 4. The influence of different feeding strategy on survival, growth, and intestine and liver development of maraena whitefish larvae is being shown in chapter 5. The effect of various weaning time and co-feeding duration on growth and survival of peled larvae is described in chapter 6. The effect of variable water oxygen saturation on growth and haematological profile of peled juveniles is shown in chapter 7. The prevalence of deformities in intensively reared peled and comparative morphometry in intensively reared fish compared to pond-reared fish is described in chapter 8. Ph.D. thesis contains important advices which can be used in fishery practise and at the same time they can prevent from elevated fish mortality.
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The issue of juvenile criminal justice
Pošíková, Lenka ; Jelínek, Jiří (advisor) ; Vanduchová, Marie (referee)
of the master thesis The issue of criminal juvenile justice The thesis deals with problems of criminal justice over juveniles. The purpose of the study is to bring an objective view of actual legal regulation in The Juvenile Justice Act No. 218/2003 and to identify problematic aspects of the juvenile justice system. Legal regulation is based upon the principle not to punish juvenile delinquents in repressive way, but to eliminate negative influences. The reason for my research is to discover the main causes of children's criminality and to outline their possible solutions. I focus on two big areas in the study - problems of the juvenile criminal liability and the system of legal instruments as a reaction of society to delinquency. The thesis is divided into six chapters; each chapter is further divided into several more subchapters according to a logical succession of addressed problems. In the first chapter I define basic terms, which are important to understand these issues. These definitions come out of the Juvenile Justice Act. Chapter two describes historical development of the juvenile legislation from 1931 to present time. The chapter consists of four parts. The main attention is given to actual legal regulation in The Juvenile Justice Act No. 218/2003. I try to show the defects of previous...
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