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Možnosti intenzivního chovu hlavatky podunajské (\kur{Hucho hucho}) v RAS
MAREŠ, Michal
This bachelor's thesis deals with the possibilities of breeding Danube salmon in the RAS, and also deals with the combination of breeding Danube salmon with rainbow trout. The fish were divided into three groups, with each group reared in three tanks. The first group was a monoculture of Danube salmon, where 160 Danube salmon with an average weight of 432.37 ? 116.01 g were put into each tank. The second group was a monoculture of rainbow trout, where 160 rainbow trout with an average weight of 253 were put into each tank. 27 ? 61.77 g. The third group was a biculture of Danube salmon with rainbow trout, where 80 trout with an average weight of 250.74 ? 61.91 g and 80 Danube salmon with an average weight of 435.04 were placed in each tank ? 119.29 g. The experiment lasted 84 days at an average temperature of 17.43 ? 0.51°C (7:00) and 17.16 ? 0.56 °C (15:00), control refishing and re-weighing was done every 28 days. At the beginning and at the end of the experiment, several pieces of fish from each group were dissected to calculate organosomatic indices, and biometric measurements were made, where the total body length of the fish (TL), the standard body length of the fish (SL) and the weight of the fish (BW) were determined. After the end of the experiment, the production markers (TL, SL, BW, FC, CVBW, SGR, FCR, WG, FE and SR) and organosomatic indices (SSI, HSI, IPF and GSI) were evaluated. In all production markers rainbow trout achieved significantly better values than Danube salmon in both farming methods. Rainbow trout dominated the biculture, using the presented feed more efficiently at the expense of the Danube salmon, as it was more aggressive and active during feeding. According to the results of the organosomatic indices, once again rainbow trout prospered best in both methods of farming. There was a marked difference in the index of intraperitoneal fat (IPF) between Danube salmon and rainbow trout in biculture. The Danube salmon in biculture achieved a better result than the rainbow trout only for the gonadosomatic index. There was a difference in the spleenosomatic index (SSI) for both species. The SSI value was highest in the Danube salmon in the monoculture, which indicates that the Danube salmon in the biculture was more limited in its food source.
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Influence of feeding management on intensive breeding of pikeperch (Sander lucoperca)
KUČERA, Václav
This thesis is aimed on problematics of intensive pikeperch aquaculture and the influence of the feeding by different types of pellets and also different frequencies of feeding during the day. Whole thesis consists of two separate experiments. In the first experiment I tried to evaluate the influence of sinking and floating type of pellets on the growth abilities and production markers of juvenile pikeperch. First experiment was stocked with 8000 pcs of juvenile pikeperch (average weight 21,38g). These fish were kept in controlled conditions for 16 weeks (average temperature of 21,37 ? 0,66 °C (7:00) and 20,77 ? 0,55 °C (15:00), average dissolved oxygen levels of 127,43 ? 2,37 % (7:00) and 117,03 ? 1,14% (15:00) °C, 120 % and initial biomass of 13,42 kg/m?). These fish were fed by belt feeders two types of pellets (floating Skretting Europa and sinking Biomar Effico Sigma) with the same nutrient composition. After 16 weeks all the production markers (SGR, FCR, WG, TL, CF and survival) were examined. Almost all the parameters showed the statistically significant difference in favor of the sinking pellets. Although growth heterogenity turned out to be lower in the group fed by floating pellets. In the second experiment 600 individuals of juvenile pikeperch with average weight of 37,49 g were stocked in tanks. These fish were kept in controlled conditions for 6 weeks (average temperature of 21,37 ? 0,66 °C (7:00) and 20,96 ? 0,66 °C (15:00), average dissolved oxygen levels of 127,43 ? 2,37 % (7:00) and 117,03 ? 1,14 % (15:00) with initial biomass of 13,35 kg/m?). These fish were fed by automatic feeder Imetronic Self Feeder in 3 different frequencies a day (3,6 or 12 batches). Pellets Skretting Europa- 15F were used in this experiment. After 6 weeks of rearing production markers were examined. Growth heterogenity, somatic indexes, and fin erosion were also examined. Also, blood samples were taken. After data analysis no statistically significant difference was found among the production markers in all three groups. Growth heterogenity was proven to be the lowest in the group fed 3x a day and highest in the group fed 12x a day. Organosomatic indexes showed statistically significant difference of HSI (hepatosomatic index). Highest index was observed in group fed 3x a day. During the analysis of the data from biochemical analysis increased levels of albumins and tryglicerids were observed especially in the group fed 12x a day. Simultaneously, statistically significant differences among the amonia levels (lowest concentration in the group fed 3x a day and highest in group fed 12x a day) and glucose (lowest concentration in the group fed 3x a day, two other groups had almost the same level of glucose) levels in plasma were found. As a group with the best results was determined a group fed 6x a day. This group reached satisfying results in production markers (better than group fed 3x a day but slightly worse than group fed 12x a day). Also, lower growth heterogenity than in group fed 12x a day was observed. Group fed 6x a day also displayed the best working lipid metabolism in contrary to the group fed 12x a day which displayed the disorder of the lipid metabolism. Also, the fin erosion was slightly lower than in a group fed 12x a day.
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Critical swimming speed in intensively cultured European perch (\kur{Perca fluviatilis} L.): Influence of fish size, production system and repeated testing
TOMÁŠEK, Ondřej
Critical swimming speed and swimming performance in relation with different factors were tested this thesis in groups of European perch (Perca fluviatilis) with focus to utilize these results in intensive aquaculture. Thesis is consisted of four different experiments performed in swimming tunnel. In the first experiment were tested, if there are any differences in day distances of measuring between three groups of fish. Each group were measured three times. First group was measured in time (t) 0, 24 and 48 h, second group was measured in time (t) 0, 48 and 96 h. Finally, third group was measured in time (t) 0, 96 and 192 h. Second experiment was set to compare critical swimming speed in three weight categories of a fish. Weight categories of 100g, 200g and 250g were tested. In the third experiment were tested pond reared fish and aquaculture (RAS) reared fish. Results were compared together, if there are any differences. Last experiment was set to find out if there is any relationship between level of critical swimming speed and somatic indexes or fillet and caraccas yield. No one of experiments performed confirm expectations of results. In the first experiment was found that there no effect of repeated swimming tests on critical swimming speed as well as no effect of different recovery period (from previous test). In comparison of different weight categories were measured highest levels of critical swimming speed in 100g group without decreasing trend in for bigger size categories (200 and 250 g). Pond and intensively reared fish had same level in critical swimming speed. Moreover, fourth experiment did not confirm influence level of critical swimming speed to somatic indexes or fillet yield. Results of presented thesis can contribute on better technical design of rearing units for this gastronomically and economically interesting species in intensive aquaculture, mainly in RAS systems.
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Inovativní metody v chovu a reprodukci candáta obecného (Sander lucioperca)
BLECHA, Miroslav
The whole Ph.D. thesis includes in total 10 chapters on 146 pages. Chapter 2 9 are specific parts of thesis where following scientific and practical aspects of pikeperch reproduction biology and aquaculture are described. Quality and quantity of pikeperch spermatozoa after varying cold water treatments are presented in the chapter 2 and can help to optimize broodstock management of males with the aim to obtain high quality spermatozoa during a seasonal and an out of season spawning as well. Benefits of hormone treatment of both sexes in semi-artificial reproduction in pikeperch are described in the chapter 3 where the importance of hormonal treatment of both sexes in tank spawning is evaluated for effective production pikeperch larvae. The use of an alcalase treatment for the elimination of pikeperch egg stickiness is being shown in the chapter 4 of this thesis. Post-ovulatory oocyte ageing and its effect on eggs viability rates and occurrence of larval malformations and ploidy anomalies are listed in chapter 5. These results describe the effects of the egg over ripening fertilization process in pikeperch. The first report of heat shock triploidisation in pikeperch is described in chapter 6 with production of 100% pikeperch triploid population. The effect of water surface treatment on survival, swim bladder inflation and growth of larvae is given in the chapter 7 with the aim to optimize the intensive culture of pikeperch larvae. Last two chapters (8 and 9) are describing the adaptation of intensively cultured juveniles to pond culture and the adaptation of pond-cultured juveniles to RAS as a new and effective methods for ongrowing production of pikeperch. In total, four published scientific papers, one handbook, one accepted scientific paper for publication, and two prepared scientific manuscripts are included and discussed in this Ph.D. thesis.
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Vliv délky světelného dne na příjem krmiva a růst síha peledě (Coregonus peled) v intenzivním chovu
KOS, Martin
The effect of the length of the daylight on growth of in peled (Coregonus peled) juveniles was tested in the intensive culture. Fish of mean body weight 1.82 +- 0.48 g and total length of 65 +- 7 mm were divided into four groups (the ratio of light and darkness 12k12, 16k8, 20k4, 24k0). The experiment lasted for sixty-three days. Every twenty-one days fishes were sampled for biometric measurements. Fish reached mean body weight of 15 +- 4.9 g (12k12); 15.6 +- 4.5 g (16k8); 16.7 +- 4.5 g (20k4); 16.8 +- 5 g (24k0) in experimental groups. The longest total body length was detected in both 20k4 and 24k0 groups (127 +- 11 mm). The lowest one was registered in the 16k8 (114 +- 11 mm). The highest condition coefficient had group 16k8 and lowest was found out in group 20k4. Specific growth rate during the course of the experiment was 3.33 %xday -1 (12k12); 3.28 %xday -1 (16k8); 3.49 %xday -1 (20k4) and 3.43 % xday -1 (24k0). The highest final survival (95.8 +- 1.4 %) was achieved in group 12k12. On the contrary, group 16k8 showed lowest survival of 90.0 +- 4.6 %. There were no significant differences in final survival rate.
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Effect of origin perch (Perca fluviatilis) at the rate of its growth in the larval rearing period of life under laboratory conditions
SMRT, Jakub
The aim of this study was to test the hypothesis that consists of the idea that the geographic origin of perch (Perca fluviatilis L.) has an impact on their adaptation to the conditions of intensive aquaculture and grow in these conditions. In the experiment perch they were tested up to the age 56 days. We tested 18 populations of perch, 6 from the Czech Republic, 5 from Poland, three from Germany, two from Finland and the population of Bulgaria and Slovakia. Experiments have shown that the geographical origin of the fish affects their adaptation and growth. The best group appeared Finnish population from the lake Valkajarvi (463 ? 21 mg) as the worst then the Polish population Zator (238 ? 26 mg). Polish population at the end of the experiment showed a 48.6% lower weight compared to the group from Finland.
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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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