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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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The state of commercial aquaponic farms in the Czech Republic
VONDRUŠKA, Vojtěch
The aim of this thesis was to conduct a literature search focused on the issue of commercial aquaponic systems and to analyse commercial aquaponic systems in the Czech Republic. In the second part of the thesis the shortcomings of the commercial aquaponic system in Řisuty were identified and described in detail. In cooperation with Aerolux s.r.o., one of these systems was rebuilt, optimized, and experimentally compared with one of the original systems.
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Výhody a další perspektivy využití smíšené obsádky pstruha duhového (Oncorhynchus mykiss) a mníka jednovousého (Lota lota) v podmínkách intenzivní akvakultury
PROFANT, Vít
This diploma thesis was focused on the culture of rainbow trout (Oncorhynchus mykiss) in combination with burbot (Lota lota) in the Recirculation Aquaculture System (RAS). Production growth indicators, the amount of accumulated undissolved substances and their chemical analysis were compared. In addition, indexes, biochemical analysis and oxidative stress were compared between the experimental groups of burbot. Three groups were tested in the three repetitions. The first experimental group (70/30) contained 70 pieces of trout and 30 pieces of burbot, in the second group (85/15) there were 85 pieces of trout and 15 pieces of burbot and in the last third group (100/0) there were 100 pieces of trout and 0 pieces burbot. The experiment lasted 77 days and control overfishing and weighing, including collection of accumulated undissolved substances, took place on days 21, 42, 63, and 77, when the experiment was terminated. At the beginning and at the end of the experiment, the total length (TL), standard length (SL) and weight (W) were measured for both species. The average water temperature was 17, 91 ? 0.48 ° C and the light period was 12L: 12D, with an average light intensity of 150 lux. Almost no mortality was reported for rainbow trout, but for burbot the mortality was 10% in the group (70/30) and 24.4% in the group (85/15). The SGR for rainbow trout was the significantly highest in the group 70/30 in I. and II. experiment period. The FCR value occurred at the end of IV. period to decrease 0.2 in group 70/30 compared to group 100/0, but there was no statistical difference. Based on data from this experiment regarding biomass and weight of individual fish, rainbow trout has clearly outgrown burbot across all periods. The same result was seen for TL, SL, W and Fulton's condition factor (FC). In the group (70/30), the amount of accumulated undissolved substances in one day was statistically significantly reduced at the end of III. and IV. experiment period. The same result was obtained for the relative amount of undissolved substances in relation to the feed ration used. According to the chemical analysis of the collected undissolved substances, there was a significant reduction in the absolute amount of dry matter and organic dry matter in IV. experimental period. The reduction of the absolute amount of phosphorus and the improvement of its retention based on the relative amount of total phosphorus in the undissolved substances with respect to the amount of feed was confirmed at the end of III. and IV. period in group 70/30. 93 There were significant differences in burbot between groups 70/30 and 85/15 in spleen somatic index, oxidative stress in the intestine, and phosphorus levels in blood plasma. These values were higher in burbot in the group (70/30), indicating that burbot in this group were more limited by the food source. According to the mentioned results, the 70/30 group was considered like the most advantageous in comparison with the other tested groups with regarding to the amount of collected undissolved substances and nutrient retention. On the other hand, in terms of welfare and physiological condition of the burbot, the 85/15 group was better evaluated compared to the 70/30 group. In general, burbot can be considered as a new potential species according to this testing in order to more diversify of freshwater aquaculture.
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Diet of Eurasian otter (Lutra lutra) in relation to the stocking of brown trout (Salmo trutta m. fario) and grayling (Thymallus thymallus)
Lyach, Roman ; Čech, Martin (advisor) ; Poledník, Lukáš (referee)
This study aimed to evaluate otter predation on stocked trout and grayling. The diet composition of piscivorous Eurasian otters (Lutra lutra) was studied on the stream Chotýšanka in central Bohemia using spraint (otter faeces) analysis during one winter period (90 days). Stocking took place mostly in the second half of 2005. Around 5000 hatchery-reared brown trouts (Salmo trutta m. fario) of size about 10 cm, 600 graylings (Thymallus thymallus) of the same size and 480 rainbow trouts (Oncorhynchus mykiss) of size about 30 cm were stocked into the stream. Spraints were collected in December 2005 and January 2006. We found and identified 1531 fish in the spraints. The primary food source of otters was fish (almost 85 % of biomass). The main fish prey was small - sized, below 20 g in weight and 13 cm in length. The bulk of otter's diet consisted of less - valued species, especially the gudgeon (Gobio gobio). Other frequently consumed fish species were the European chub (Squalius cephalus), the common carp (Cyprinus carpio), the European perch (Perca fluviatilis), the brown trout and the rainbow trout. Consumption of stocked brown trout was 1,80 %, while cosumption of stocked rainbow trout was 10,90 % of biomass. Otters in this area consumed about 723 - 1446 brown trouts and 72 - 144 rainbow trouts...
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Vliv původu a strategie chovu lososovitých ryb na dosahované produkční parametry
Kudláček, Josef
Selection of adequate genetic material and the right breeding strategy are some of the basic factors affecting success of salmonid fish breeding. The study is focused on a comparison of several populations of rainbow trout with different origin and breeding strategies. Data from reports of The Czech Fish Farmers Association and Diplomas Thesis related to given issue were used. Growth rates, survival and yield were the main criteria for evaluation. In the first part, data from several years monitoring of trout breeding at Annín were processed. At Annín was observed the influence of artificial selection on production parameters of rainbow trout line Pd75. Results show that selected populations reached 8.64 % of average selection profit. At the second part, data from five-year monitoring at Velká Losenice were analysed. Two populations of rainbow trout (PdMar93 a PdM) were compared. The obtained results showed better growth and 4 % higher yield in case of PdMar93. At the third part, focus was on comparison among different strategies of fish breeding in the Czech Republic. According to results suitably selected feed and climate conditions showed high influence. In some cases, significant influence of chosen species for breeding was detected. The best parameters achieved hybrids of Salvelinus compared to rainbow trout. Suitable chosen genetic material and breeding strategy can highly affect production parameters of farmed fish, consequently and economy of farming.
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Vliv původu a podmínek chovu lososovitých ryb na jejich nutriční hodnotu
Urban, Michal
The objective of this thesis is judging the influence of selected factors on nutrient value and exterior indicators of salmonids. These factors are enviroment, rearing con-ditions, nourishment and origin of fish. The context between factors and nutrient value was evaluated by literary sources. Practical part is based on data from feeding test. The feeding test was realised in farm Bušanovice on Autumn 2017. Three diferent feeds were fed to six groups of fish. Experimental feed with mineral component named Klinolipolit and two improted commercially produced feeds. I participated on the chemical analysis of the fish samples. The differences betwe-en groups of fish fed with different feeds was evalueted by results from chemical ana-lysis and data from weight and lenght measurement.
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Vliv původu a strategie chovu na nutriční hodnotu produkovaných lososovitých ryb.
Trybulovský, Filip
In my work, I was dealing with the influence of the origin and strategies of breeding of produced salmonid fish on the nutrition value of the muscle. Rainbow trout, brook trout and interspecific hybrid of Salvelinus alpinus and S. fontinalis were analyzed. Two feed tests were performed. Both tests were carried out in an experimental recirculating system at the Department of Fisheries and Hydrobiology at the Mendel University in Brno. Length-weight parameters of fish were measured, from which individual indices, production and conditional parameters were subsequently calculated. In addition, the yield and viscerosomatic index were determined. The content of fat, proteins and dry matter of the fish muscle was determined and used for nutrition value evaluation. The effect of reduced oxygen saturation (below 70 %) compared to normal oxygen saturation (around 100 %) was also analyzed in the first test. In Test 1, feedstuff Biomar Efico Enviro 920, Focus Plus with the addition of immunostimulants and Advance with a higher proportion of plant components were used. No statistically significant differences in production and conditional parameters, length-weight ratios and yields were registered for these feeds. The highest percentage of fat content in the muscle (7.66 %) was in fish fed Focus Plus. The dry matter and protein content of the muscle was similar. The greatest effect of reduced O2 was noticed in the fat content of the muscle. For a group of fish fed Efico Enviro 920, it was statistically significant (p = 0.03 and 0.042). Yield values were higher in a group with reduced oxygen saturation. This could be the result of lower intake of feed at the reduced O2 and lower amount of internal fat. In Test 2, the largest difference was recorded in the percentage production of fish. The highest increase was achieved by rainbow trout in Var. 1 (238.8 %) and the lowest increase was achieved by brook trout in Var. 4 (122.43 %). No statistical significant differences in production and length-weight parameters were registered. The highest yield was recorded in the hybrid (88.47 %) in Var. 5.
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Hodnocení produkční účinnosti krmiv v chovu lososovitých ryb
Arežina, Slaven
This diploma thesis deals with the nutrition and evaluation of salmonid fish species, more precisely Riverine brown trout. In the practical part, I have dealt with two studies, by monitoring the growth of fish from 50 g to market weight and monitoring the growth of fish from 125 g to market weight. In both studies, food that was used to fed was a feed Aller gold 3 mm, Aller gold 4,5 mm and Coppens ultra 4,5 mm. In the first test, I fed fish on an average for 180 days to achieve a market weight of 268,14 g. In second test on an average for 108 days to achieve a market weight of 342,72 g. Furthermore, on these fish were performed partial tests such as the FCR fodder, the specific growth rate of the SGR, fish survival per period, cumulative fish survival, relative fish gain over the reference period, and the relative ratio of FCR/SGR. The system in which the fish were kept was flowing. As a result, the values evaluated by the software differed from the measured values, mainly because the software evaluated the values for all the ponds and only for the whole time of breeding from the input and final data, whereas I evaluated the values only for the individual ponds and the individual stages of the breeding, which take into account interventions in the pond stock. Therefore, all FCR feed rates and survival percentages differ from those measured. Deviations are noticeable in the first test, the "KASA" program evaluated the FCR at an average of 1.31 and my value was 0.93; the survival rate was 63.82% on average, and my score was 88.41%. In the second test, the results differed again for the same reason. The software evaluated the FCR on average at 0.97 and my average score was 0.94; the survival rate for the second test evaluated the program at 102.61% and my score was 97.05%. Comparing the test period, the more favorable results were obtained when using fish with an average weight of 125 g.
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Vliv přírodních extraktů na senzorické vlastnosti a prodloužení skladovatelnosti masa pstruha duhového (Oncorhynchus mykiss)
TUNYS, Ondřej
This bachelor thesis evaluates the effects of natural rosemary extract "Inolens 4" on microbiological quality, sensory attributes, colour change and oxidative effect of rainbow trout (Oncorhynchus mykiss). The evaluation is expressed in comparison with the control sample (no additive). Individual analyses took place in different days (0, 3, 6, 10 and 14 days). The microbiological analysis showed values in the range of 1.93 - 2.25; 5.10 - 5.27; 5.12 - 5.80 and 6.34 - 7.66 log CFU*g-1 on days 0, 6, 8 and 10. The limit for freshwater fish consumption (7 log CFU*g-1) was exceeded on 10th day of storage. On the contrary Inolens 0.5 achieved the best result. Sensory analyses also showed that Inolens 0.5 achieved the best results in all sensory attributes (odour, taste, aftertaste, consistency) of cooked fish. Also TBARS analysis evaluating lipid oxidation proved that the application of Inolens 4 extract had a positive effect causing an inhibition of oxidative processes in the muscle. Therefore all the results of this study have shown that the natural extract "Inolens 4" has antioxidant effects extending the storage of rainbow trout meat in combination with suitable storage (vacuum and cooling at 4 +- 1 °C) for up to 10 days. Moreover it has a mild effect on the improvement of sensory properties.
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Diet of Eurasian otter (Lutra lutra) in relation to the stocking of brown trout (Salmo trutta m. fario) and grayling (Thymallus thymallus)
Lyach, Roman ; Čech, Martin (advisor) ; Poledník, Lukáš (referee)
This study aimed to evaluate otter predation on stocked trout and grayling. The diet composition of piscivorous Eurasian otters (Lutra lutra) was studied on the stream Chotýšanka in central Bohemia using spraint (otter faeces) analysis during one winter period (90 days). Stocking took place mostly in the second half of 2005. Around 5000 hatchery-reared brown trouts (Salmo trutta m. fario) of size about 10 cm, 600 graylings (Thymallus thymallus) of the same size and 480 rainbow trouts (Oncorhynchus mykiss) of size about 30 cm were stocked into the stream. Spraints were collected in December 2005 and January 2006. We found and identified 1531 fish in the spraints. The primary food source of otters was fish (almost 85 % of biomass). The main fish prey was small - sized, below 20 g in weight and 13 cm in length. The bulk of otter's diet consisted of less - valued species, especially the gudgeon (Gobio gobio). Other frequently consumed fish species were the European chub (Squalius cephalus), the common carp (Cyprinus carpio), the European perch (Perca fluviatilis), the brown trout and the rainbow trout. Consumption of stocked brown trout was 1,80 %, while cosumption of stocked rainbow trout was 10,90 % of biomass. Otters in this area consumed about 723 - 1446 brown trouts and 72 - 144 rainbow trouts...
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