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Aplikace nanobublin ozónu v intenzivní akvakultuře
KONONOV, Maksim
The aim of this bachelor thesis was to test the effects of different ozone nanobubble concentrations (O3NB), as a new perspective method of water disinfection in aquaculture, on early ontogeny (the embryonic and larval period) of rainbow trout (Oncorchynchus mykiss) in a hatchery with a pond water (i.e. organically polluted water) source. During this work, two experiments with various O3NB concentrations ranging from 192 +- 40 to 610 +- 122 mV ORP (group 1: 192 +- 40, 2: 277 +- 104, 3: 392 +- 134 a 4: 610 +- 122 mV) in combination with two different husbandry treatments (with/without removal of dead eggs and individuals) were conducted. In the first experiment (N, groups 1-4 N), unfertilized eggs and dead individuals were not collected, in contrast to the second experiment with collection of dead individuals (S, groups 1-4 S). Testing of the above groups (1-4 N/S) was performed in four replicates (aquariums A, B, C, D). Hatching rate was higher in all tested groups of the experiment S. The highest hatching rate (approximately 75 %) was observed in groups 1S, 2S and 3S (ORP 192 +- 40 to 392 +- 134 mV ORP). Fish mortality rate was higher in all groups tested during the experiment N. The highest fish mortality rate (higher than 75 %) was observed in all groups 3N and 4N/S (ORP 392 +- 134 to 610 +- 122 mV). At hatching, the yolk sac volume negatively correlated with O3NB concentration during both experiments. The yolk sac (as an energy source) was faster fully absorbed in fish reared in groups with lower O3NB concentration in comparison with the highest O3NB treatment, when the absorption was markedly slower. The total body length of fish was significantly affected by O3NB concentration during both experiments. The slowest growth was recorded in group with the highest O3NB concentration (ORP 610 +- 122 mV) compared to other groups (ORP from 192 +- 40 to 392 +- 134 mV). The microbiological analyses showed decreasing amount of water microorganisms with increasing O3NB concentration. In summary, the O3NB concentrations in range ORP 192 +- 40 to 394 +- 134 mV), ideally in combination with treatment S, can be recommended for rearing of early stages (embryos and larvae) of rainbow trout. Further research on O3NB in aquaculture is highly required, as there is still a lack of information regarding this perspective technology.
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Porovnání populací okouna říčního (Perca fluviatilis L.) z intenzivní akvakultury - vliv původu ryb na chování a kritickou rychlost plavání.
TOMÁŠEK, Ondřej
European perch is one of potential fish for breeding in conditions of intensive aquaculture. This species of fish is in relatively high demand, especially in the Alpine region, because of its very tasty meat. The relatively high price of fillets is attractive for producers. The difficulties in perch farming in conditions of European intensive aquaculture may alleviate the further domestication process of this species or its selective breeding. These pitfalls are negatively correlated with fish welfare. In this thesis, we examined morphometric (morphometry, fin damage, somatic index), behavioural (activity, aggressivity, boldness and critical swimming speed) and physiological (cortisol, glucose, enzyme activity, potassium) parameters in four populations of perch imported from different European intensive farms (France - two farms, Hungary, Denmark) engaged in their producing. Experiments performed in this thesis showed that individuals from the Danish population has the highest activity of the studied populations, including the critical swimming speed (4.24 ? 0.15 BL.sec-1). The population from Denmark also found the highest percentage (8.9 %) of bold exploratory behaviour, which subsequently increased aggressive behaviour within this population. The number of attacks on other individuals from the flock reached the highest measured values in this experiment (2.33 ? 2.31 attacks). Furthermore, experiments showed that individuals from the Danish population showed a higher tolerance for adverse environmental problems compared to other populations from Hungary or France. These differences, which have been observed in the Danish population, can be interpreted as a proactive stress mechanism that is characteristic of fast pace syndrome (fast POLS). High perivisceral fat index was found in fish from the Hungary. The morphometric characteristics of all populations were significantly different. Genomic characteristics could address this approach in the near future, in particular to streamline domestication processes and support the selective breeding of perch suitable for European intensive aquaculture.
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Vliv pastevního odchovu na růst a kondici koně
Klabanová, Monika
This thesis deals with pasture breeding of horses and its influence on growth and fitness. The main focus is on the pasture rearing issue. Physiological characteristics, which include also growth and fitness are described first. In the next chapter of this thesis, possibilities of measuring of horses, measuring tools and principles that must be followed are presented. Pasture breeding, properly managed and equipped pastures, the composition of permanent grassland and advantages and disadvantages of pasture breeding are also described. The last chapter contains a questionnaire on the topic of pasture issues. This work is complemented by photo documentation.
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