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Odchov násady kapra v intenzivní akvakultuře
KOLAŘÍK, Filip
The common carp (Cyprinus carpio, L.) is a typical pond fish. However, intensive rearing systems aimed at rearing this fish can also be found in production aquaculture. Mainly for the rearing of two-year carp in winter. Such systems have been operated, for example, in Poland and Germany. In Poland, cage farms located on canals supplied with warmed water from the thermal power stations (Dolna Odra, Konin-Goslawice) were used. In Germany, due to the high losses on carp fry and two-year carp caused by cormorants during wintering, a similar rearing method was adopted. Breeding in flow-through systems (Schwarze pumpe, Jänschwalde) and recirculation systems (Neiden) were used. The aim of this bachelor's thesis was to evaluate and compare intensive carp broodstock rearing abroad and semi-intensive carp broodstock rearing used in the Czech Republic. At the same time, the bachelor thesis included an experiment in a recirculation system in Blatná, focused on winter rearing of two-year carp in the first year of the breeding cycle. The experiment was carried out in the recirculation system of the company Blatenská ryba s.r.o. The experiment lasted for 227 days, from the 1st of October 2021 to the 16th of May 2022. The first phase lasted from the 1st of October 2021 to the 8th of February 2022 and was accompanied by low growth and the development of lordosis. At the beginning of the phase, 6 800 carp fry were stocked into a rearing tank with a volume of 9.5 m3. The average weight of the stocked fry was 11,54 g.pcs-1. At the end of the first phase, the carp reached a weight of 50 g.pcs-1. The second phase of the experiment was conducted from February 8th, 2022 to May 16th, 2022. The phase was focused on a feeding experiment. The carp were divided into three tanks of 1,575 pieces each. Each tank was fed a different type of feed. At the end of the experiment, the best results were achieved by the fish fed with the Aller aqua Classic+Master feed type. These fish achieved a weight of 210.57 g. pcs-1 during the rearing period. However, the feed AG SV was the best economically. The worst growth and economic results were achieved in the group fed with the Skretting carpe F feeding type. Losses over the experimental period were only a few tenths of a percent. However, the whole breeding was accompanied by problems with the occurrence of lordosis in the reared fish. The occurrence of lordosis was caused by the poor composition of the feed used in the first phase of the experiment. In particular, the lack of easily digestible phosphorus for the carp. The results show that by using winter rearing it is possible to shorten the normal rearing cycle by one to two years. Compared to semi-intensive pond rearing, minimal losses are achieved. However, more emphasis must be placed on fish nutrition and the quality of the stocked fry.
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Možnosti zvýšení adaptability a prevence negativních změn v chování u násady jesetera sibiřského (Acipenser baerii)
KODRAS, Marek
The experiment was performed to assess the impact of a modification in feed technology in the intensive rearing of Siberian sturgeon (Acipenser baerii) on the fish behavior. Four feeding regimes were tested in three repetitions: surface feeding during the day (DFSF), surface feeding at night (NFSF), bottom feeding during the day (DFBF), bottom feeding at night (NFBF). Sturgeon behavior was recorded using a video system in experimental observation tank before the application of different feeding regimens at 48th days post-hatching (dph) and every 20 days therafter (68th, 88th and 108th dph). In addition, the effect of five and ten-day starvation on fish behavior was determinated. Five parameters were tested: the total time spent in the lowest 10 and 25 % of the observation tank, the total time spent in the uppermost 10 and 25 % of the observation tank and the total activity. The whole experiment including larval rearing lasted 100 days and videos were analyzed using MATLAB software. Statistical differences were observed among the tested groups during our experiment. Experimental group NFBF at 88th dph showed the highest spending time in the lowest 25 % of the tank. Furthermore, NFBF at 68th and 88th dph displayed the lowest spending time in the uppermost 25 % of tank (only NFSF was not significantly different from NFBF at 68th dph). No statistical differences were observed in the uppermost or the lowest 10 % of the tank after all-day videorecording. After starvation, some differences were observed among the groups, however no clear trend or continuity with the data obtained before the starvation were found. In conclusion, the tested group NFBF showed better preconditions for intensive rearing of sturgeons, which might be subsequently stocked in open waters due to the lowest movement in the uppermost part of the tank (68th and 88th dph) than other tested groups. This could increase survival of the fish in the wild due to lower predation risk.
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Využití odpadního tepla z bioplynové stanice pro zemědělské účely
DUFEK, Daniel
The bachelor thesis deals with utilization for waste heat, which arises during cooling of cogeneration units of biogas plant. It is a concept for technology which is able to consume some of the waste heat. In this case, it is a proposal for a complete recirculating aquaculture system for African catfish breeding, financial analysis and return of investment.
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Možnosti využití hmyzí moučky v krmivech pro candáta obecného (Sander lucioperca)
KODRAS, Marek
A feeding trial was carried out to assess the effect of replacing fish meal by partially deffated black soldier fly pre-pupae meal in feed for pikeperch (Sander lucioperca). A diet with fish meal, that covered 30 % of total protein, was used as a control. Three other diets contained 7,5%, 15% and 30% of insect meal, which coresponded to 25% (H25), 50% (H50) and 100% (H100) replacement of fish meal. Each tested group had 3 repetitions and experiment lasted 63 days. At the end of the trial, groups H25 and H50 did not show any significant statistical differences in growth and lenght performance compared to CON. There were no differences among groups in coefficient of variation, condition factor, hematocrit, feed conversion ratio, economic conversion ratio, fat and ash content in muscle. On the other hand, significant differences were observed in specific growth rate, contain of proteins in muscles, dry matter, somatic indexes and economic profit index. No differences in survival were found until 42. day. However, between 42. a 63. day of rearing high mortality caused by bacterial infection was observed in two of three tanks fed with H100 diet. This fact influenced this parameter for group H100. In conclusion, 7,5 % inclusion of insect meal from partially deffated black soldier fly pre-pupae meal, corresponding to 25% replacement of fish meal, may successfully replace fish meal in diet for pikeperch, as this substitution did not have negative influence on any parameter.
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Effective use RAS technolgy for breeding of ornamental fish in garden tanks.
MITÁŠ, Jaromír
The aim of this thesis was to evaluate the efficiency of the technology RAS for water cleaning and conditioning for ornamental tanks with an emphasis on sustainable conservation of water transparency. Initial costs for building the tank, operational costs and costs of purchasing fish were compared. Results include measurements that have been carried out on private property of the author, who breeds ornamental koi carp (Cyprinus carpio). The filtration of breeding tank was formed by vortex, by chamber with brushes, chamber with bioblocks and bioaquacitem. Tentative and 24 hours measurements of selected variables were used for data obtaining. The results indicate that the filter system is effective, but it had insufficient capacity. Transparency of water and elimination of glaucoma was solid by involving of UV lamp into the system of filtration. Available commercial resources were successfully used for controlling of filamentous algae. This thesis also includes a brief overview of ornamental fish species of our region, Moreover we mentioned the most common diseases, causative agents, symptoms and treatments. Overall, monitoring of the system of the garden's ornamental tank confirmed that water quality is dependent on the right choice and dimensioning of the filtration system and that current technology of recirculating of aquaculture systems can be successfully and effectively used within the construction and operation of tanks used for breeding of ornamental fish species.
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Testing of production efficiency during culturing of market size of North African catfish (\kur{Clarias gariepinus}) using specialized feeds with an substitute of fish meal in semioperational conditions of RAS
HOUDA, Ondřej
There was considered production efficiency of three kinds of feeds with a partial substitute of fish meal specified to intensive culturing of "catfishes" in North African catfish in semioperational conditions of RAS in present BSc. thesis. There were made use of feeds by the Dutch company Coppens (CATCO SELECT - 13EF, CATCO GROWER - 12EF) and feed by the Hungarian company Haltáp. The individual feeds differed particularly from the contents of fat and from the contents and the origin of a proteinous component. The temperature in the course of the whole experiment was 24.5 ? 0.95 °C (mean ? S.D.), pH was 7.2 ? 0.34 and the content of dissolved oxygen was 2.4 ? 0.34 mg ? 1 O2. The experiment was divided into three particular feeding periods 20 days at a time and it took 63 days in total. The size of optimal relative daily ration served to fish along the line of the experimental attempt made in the event of feed SELECT - 13EF 1.40 ? 0.29 % (mean ? S.D.), GROWER - 12EF 1.28 ? 0.21 % and Haltáp 1.94 ? 0.06 %. Next production parameters were followed in the course of own attempt: individual weight, stocking density of tank, specific growth rate (SGR), food conversation ratio (FCR), protein efficiency ratio (PER), gonadosomatic index (GSI), Fulton's coefficient of condition and utilisation rate. Average stocking density of fish in tank was 53.49 ? 0.36 kg ? m-3 at the start of the experiment and 168.75 ? 12.23 kg ? m-3 at the end. Average individual weight of fish at the beginning of the experiment was 269.64 ? 10 g and by the end 642.85 ? 55 g. In the course of testing it came to average increase in individual weight approximately 2.4 times. Resulting mortality along the line of the experimental period was on level 1.25 %. The hightest achieved SGR was discovered at the group feeded by feed SELECT - 13EF (1.58 ? 0.41 % ? d-1), the group feeded by feed Haltáp came after (1.38 ? 0.38 % ? d-1). The most favourable values FCR were achieved by use of feed SELECT - 13EF (0.83 ? 0.02), the group feeded by feed GROWER - 12EF (87 ? 0.01) followed, the worst result was achieved by use of feed Haltáp (1.37 ? 0.13). The most favourable values PER were achieved at fish feeded by feed SELECT - 13EF (2.89 ? 0.08), feed GROWER - 12EF (2.54 ? 0.04) followed and the worst results were found out by use of feed Haltáp (1.65 ? 0.14). GSI was growing on average five times higher values (2.65 ? 1.34) at females than at males (0.53 ? 0.26). The difference of achieved GSI depending on used feed was not found. Fulton's coefficient of condition acquired average value at females 1.09 ? 0.10 and at males 1.06 ? 0.07. Average value of utilisation rate acquired at females 39.96 ? 1.26 % and at males 40.46 ? 2.33 %. The lowest expense per weight gain (evaluated for increase of 1 kg) were noticed at feed Haltáp (41.33,- CZK), feed SELECT - 13EF (41.98,- CZK) came after and feed GROWER - 12EF proved to be (44.02,- CZK) the worst. The review of analyses of organoleptic qualities (consistence, smell, taste and aftertaste) and the preferential analyses did not show any significant, demonstrable influence of used feed on quality of gained flesh. Evaluators (35.77 % of respondents) labeled the sample of muscle of catfish feeded by feed Coppens CATCO SELECT - 13EF as the most delicious.
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