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Optimalization of artificial incubation of eggs and embryos in northern pike (\kur{Esox lucius L.}) under controlled conditions
HAMPL, Jan
Within my diploma thesis I have been trying to resolve the possibilities of optimization of artificial incubation of eggs and embryos in northern pike (Esox Lucius L.) under controlled conditions during three different experiments. In the first experiment was investigated the effect of three different semination solutions to the success of incubation of eggs and embryos in northern pike. I watched the survival of eggs and embryos, larvae hatching abnormalities and biometrics of larvae. It was found that the best overall results were achieved with semination solution composed of 15 ml of chemical crystalic urea per 1 liter of water, with an appropriate amount of abnormalities and highest larvae survival. In the second experiment were performed manipulation with developing eggs at given time intervals after fertilization of eggs. I watched the survival of eggs and embryos, abnormality and biometrics of hatched larvae. It was found that the lowest survival, abnormalities, and smallest TL and W were reached during manipulations within 24 hours after fertilization. In the third experiment was investigated the effect of water temperature on the length of the incubation of eggs and embryos in northern pike. With regard to the overall survival, larvae hatching, abnormalities and size of larvae achieved the best results temperatures 6 and 10 ° C. Conversely, it is entirely unsuitable for incubation temperature of 3 ° C (lowest survival, large amounts deformities). Different incubation temperatures have also confirmed the effect of water temperature on biometrics of hatched larvae.
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Predictive models in survival analysis
Hadwigerová, Michaela ; Vítek, Martin (referee) ; Škutková, Helena (advisor)
With ever-new methods of treatment in health care occures a requierement of comparing these new methods to the old methods in some effective way. This is particularly important for the further development of these methods. However, data that describe these facts could not be processed by normal procedures and therefore was in the field of statistics to create a new kind of methods. They are known as predictive models of survival analysis.
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Water temperature influence on the success of intensive farming of burbot (Lota lota L.)
CHOTĚBORSKÝ, Michal
The aim of this work was to realize the first intensive rearing of juvenile fish of burbot in the Czech Republic (TL = 165.79 +- 18.87, W = 32.91 +- 10.27 g) in recirculation aquaculture system (RAS) at different water temperatures. A total of 9 tanks were used in the three separate RAS systems. For a period of 12 weeks survival (S), specific growth rate (SGR), feed conversion ratio (FCR) and the condition of the fish (FC) was observed at 3 week intervals. The best values of survival (98 +- 0.4%) were achieved in burbots kept at a water temperature of 15 ° C. Survival in the group of fish kept at a water temperature of 18 °C did not statistically differ from the group of fish reared at 15 °C and 21 °C. The SGR value for the fish at a water temperature of 15 °C was (0.7 +- 0.09%.d-1) at 18 °C the SGR value was (0.45 +- 0.1%.d-1) and fish kept at a water temperature of 21 °C reached SGR values of 0.33 +- 0.04%.d-1. The best FCR values (1.27 +- 0.35) were reached also in the group of fish kept at 15 °C. For burbot kept at a water temperature of 21 °C, the FCR value was 2.78 +- 1.17. Based on our results we can conclude that the most appropriate water temperature for rearing juvenile burbot was 15 °C.
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Growth and survival of pearl mussel (Margaritifera margaritifera) for bioindication
NIEDLOVÁ, Eva
Growth and survival of juvenile pearl mussels (Margaritifera margaritifera Linnaeus, 1758) "in-situ" indicates suitable habitats for their rearing and subsequent reintroduction. Six streams in Aš region (Rokytnice, Lužní potok, Pekelský potok, Újezdský potok, Perlový potok, Bockbach) including 15 profiles were evaluated throughout the season (1. 6. 31. 8. 2015). One year old pearl mussels (n = 580) sized from 700 1400 ?m. Mean survival of pearl mussels was 63 % in all streams. Mean absolute growth increment attained 755 ?m throughout the season. Growth of pearl mussels (1+) was positively correlated with the water temperature (R2 = 0,1084). Both the highest survival (70 %) and the highest absolute growth (1027 ?m and 997 ?m) of pearl mussels was determined on localities in Bockbach (Bockbach 11 and 1). In contrast to Bockbach 11 and 1 mean survival (28%) and absolute growth (304 ?m) was the lowest in Lužní potok 2. Survival rate of two years old pearl mussels was higher than that of one year old pearl mussels. Both of these age categories grew similarly.
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The optimization of transfer Northern whitefish larvae (Coregonus peled) on complete feed mixture.
PITHARDT, Tomáš
In this work was tested optimal rearing protocol for Northern whitefish larvae in two experiments. Both experiments lasted for 34 days. In the first experiment the effect of feed particle size on the survival and growth were tested in Northern whitefish larvae with initial body weight of 3.01 +- 0.48 mg. Larvae were weaned from live feed 10th, 15th, 20th, 25th and 30th day after hatching when co-feeding was took for 3 days before the weaning. In the first experiment were tested particle size of 100 micrometers and 300 micrometers. Groups weaned 20th, 25th and 30th with 100 micrometers feed and groups weaned 25th and 30th with 300 micrometers feed had similar final survival (without significant differences). The best growth (final weight 39 +- 12 mg) had group weaned 30th day after hatching using particle size of 300 micrometers. In the second experiment the effect of length of combined feeding (co-feeding) on the survival and growth were tested in Northern whitefish larvae on a unit weight 3.01 +- 0.48 mg. Co-feeding lasted for 1, 3 or 6 days before the weaning. Larvae were weaned from live feed 10th, 15th, 20th, 25th and 30th days after hatching. Groups weaned 10th, 15th, 20th, 25th and 30th had similar final survival (without significant differences). But the best growth (final weight 37 +- 15 mg) reached group weaned 30th day after hatching with combined feeding for one day. Groups weaned 20th, 25th and 30th had similar final body weight (without significant differences). There was no observed effect of co-feeding duration on survival and growth.
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The effect of feeding frequency on feed intake and growth for Peled whitefish (Coregonus peled) in intensive aquaculture.
DOFEK, Jan
Frequency influence of animal feed has been tested (6×, 4×, 2× and 1× per day). Food income and new arrival experiment was repeat in three phases after every 21 days. Fish age after 124 - 187 days from the beginning till the end of the experiment. Average weight in all tanks was 1.86 + - 0.5 g in first experiment phase (0. 21. days). At the end of first experiment fishes with the biggest weight were the one with frequency influence of animal feed 6 times a day. Individual weight at the end of first fishing was 4.21 + - 1.31 g (6× a day), 3.74 + - 1.24 g (4× a day), 3.6 + - 0.46 g (2× a day), 2.89 + - 1.29 (1× a day). The best growth group become group with frequency influence (6× a day and 4× a day) and on the other hand group with the smallest growth was the group with frequency influence (1× a day). Fishes achieved weight of 15.9 + - 4.5 g (6× per day), 15.1 + - 4.9 g (4× per day), 12.19 + - 5.4 g (2× per day), 5.54 + - 4.05 g (1× per day). Chance of survival (96 %) was the best in group with frequency influence of animal feed (4× a day) and the last (89 %) was the group with frequency influence (6× a day). The highest rate of heterogeneity (74 + - 9 %) was in third phase of experiment in fish group with frequency influence (1× a day) as compared to group (28 + - 2 %) with frequency influence of animal feed (6× a day).
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The effect of water temperature on early ontogeny in African catfish (Clarias gariepinus)during post - embryonic development
FRANTA, Pavel
This theses is made up from two methodologically identical experiments, which involved observing the starting time of key sections of early ontogeny (H95, S95, Re95) at a temperature of 24°C. The experiments used 29 groups of eleuterembryoes/larvae which were fed for 30 days, but timing of initial feeding of exogenous food was different between the groups. The first group began initial feeding at the age 72 hPF and every other group was fed for the first time 6 hours later than the previous group (the last group was fed at the first time at the age 240 hPF). The group, which wasn´t fed exogenous food during the experiment, served as control. The effect of timing of start feeding on morphometric and gravimetric characteristics, size distribution, survival and rate of cannibalism in eleuterembryoes/larvae was examined. A temperature of 24 °C was determined the hatching time of eleuterembryoes after 36, resp. 33 hours (1st, respectively 2nd experiment) from fertilization. The start of intake of exogenous food (S95) was determined at age 123 hPF, yolk sac absorption at age 150 hPF during the 1st experiment. At the 2nd experiment the start of intake exogenous food was determined at age 115 hPF and yolk sac absorption at age 161 hPF. During the interval from H95 to S95 records showed an increased rate of growth, especially the caudal part of the body. At the age from S95 to Re95, growth of unfed larvae was stopped (first effect of starvation). Almost all monitored parametres were significantly affected (P < 0,01) by timing of start feeding except for rate of cannibalism. While the percentage representation of large sized and medium sized individuals (the potential cannibals) was decreased with increasing the time of start feeding, the rate of cannibalism wasn´t changed. However the number of small sized individuals was increased with increasing the time of start feeding. The study of the African catfish confirmed the negative impact on survival, which is caused by a delay in initial feeding. Unlike survival, with morphometric parametres there wasn´t observed a significant decrease in values, provide the larvae was first fed before reaching the age of 216 hPF. It was also found that almost 100 % of the individuals in the control (unfed) group died at age 377 hPF. However the first indications of increasing mortality was observed in age 283 hPF. Based on the above information, the PNR (point of no return) was reached approximately at the age of 270 hPF in African catfish
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Optimization of harvest of juveniles of pikeperch (\kur{Sander lucioperca}) taken out of ponds and following ability of the fish to adapt to system RAS
HAMPL, Jan
Within my bachelor thesis I have been trying to resolve the possibilities of optimization of harvest of juveniles of pikeperch (Sander lucioperca) taken out of ponds, and continuously I have been tracking the ability of the fish to adapt to system RAS that is applied at the experimental fish culture facilities at FROV JU. Working at the fish harvest it has shown me to be important to synchronize the work of every one of the assistants during the individual activities. The fish have been harvested in a very short time and carefully taken to already prepared transport boxes. We checked the most important parameters for the quality of water, its temperature and oxygen saturation. The mortality of the fish during the harvest and transport did not get over 2 %. Just after the transport to experimental fish culture facilities at FROV JU, to the system RAS at Vodnany, the harvested fish has been placed to 9 tanks for the weaning period. Each out of three ponds always received three tanks of harvested and adapted fish. The experiment at RAS has been divided into three parts. First part has been about the weaning period of the fish to the RAS system and the artificial food. The results were very satisfying. I have been following these parameters: SGR, FCR, increase of biomass, survival and cannibalism at the tanks. The level of survival from the pond Rohlíček has been around 83,6 %, the pond Bejkovna 69,7 % and Horažďovice 4 the level of survival was 71,8 %. After finalizing the weaning period we did biometry for 37 of selected representatives. Second part has been the 1st post-weaning period. Here I focused at the parameters such as SGR, FCR, increase of biomass, survival and cannibalism at the tanks. The level of survival from the pond Rohlíček has been around 84,17 %, the pond Bejkovna 83,83 % and Horažďovice 4 the level of survival was 82,83 %. After finalizing the 1st post-weaning period we did biometry for 37 of selected representatives. Third part has been the 2nd post-weaning period. Here I focused at the same parameters as above such as SGR, FCR, increase of biomass, survival and cannibalism at the tanks. The level of survival from the pond Rohlíček has been around 87,5 %, the pond Bejkovna 88,17 % and Horažďovice 4 the level of survival was 87,17 %. After finalizing the 2nd post-weaning period we did biometry for 37 of selected representatives, the experiment was evaluated and pikeperch juveniles were sold to the French company Asialor.
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Cold hardiness of larvae of the fruit fly, \kur{Drosophila melanogaster} (Diptera: Drosophilidae)
KORBELOVÁ, Jaroslava
We assessed survival of larvae of the fruit fly, Drosophila melanogaster at low temperatures (0°C and 5°C) after rearing them under seven different acclimation regimes. Larvae that have developed in a standard diet at 25°C showed 50% mortality after 12,6 min of the exposure to 0°C (Lt50 = 0.21 h). In contrast, larvae that have developed in a diet enriched with glycerol at 15°C, and were cold acclimated at 5°C during last two days of their development, had Lt50 = 38.6 h. It means that it was possible to increase the Lt50 at 0°C more than 180-fold using simple manipulations with rearing temperatures and diet composition. The physiological differences in duration of larval development, fresh mass, dry mass, hydration and total contents of proteins, lipids and glycogen between the larvae belonging to different acclimation variants are described. The samples for future detailed metabolomic analysis were prepared.
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