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Rozvoj zooplanktonu v rybnících s produkcí rychlených stádií hospodářsky významných druhů ryb
PECHA, Oldřich
This master thesis was focused on zooplankton development in ponds with advanced fry rearing of economically important fish species. For the purpose of my study, we sampled pond cascade that is managed by Štičí líheň - ESOX, spol. s r.o. in the village Liderovice, near Tábor. In this particular pond cascade, the annual production of advanced fry of economically important fish species takes place, namely pike, pikeperch, carp, tench and grass carp. Importantly, pond cascade is used several times during one growing season, and zooplankton is the main food source of all early stages of rared fish. For the production of advanced fry of fish served 3 ponds, which were released and refilled 2-3 times a season. Fourth pond served as a control stocked with one year old carp throughout the whole season. The water from an upper pond in the cascade served as zooplankton inoculum to a lower pond after the pond harvesting. Statistical analyses showed that the fry of different fish species in ponds lying in the same cascade does not affect the composition of zooplankton after restocking and water refilling. The only difference we noticed was in the treatment with pikeperch, which partially does not share the food base of other monitored species.We also found out, that the occurrence of Cyclops vicinus, Daphnia magna, D. ambigua or D. pulicaria was positively correlated with increased P-PO4 concentrations. We also confirmed that pond ecosystem can effectively retain nutrients from basins and use them for its production. As was shown after a short rain when the measured concentration of total phosphorus in the inflow in our pond system was 0.50 mg/L, on the contrary in the last pond of our cascade we measured values below 0.08 mg/L. High transparency was maintained in the whole cascade throughout the monitoring period, and an adequate economic profit was generated. Such management can be applied to only a few ponds (systems).
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The Tench Fertility and Condition Changes in Fishery HLuboká
ŠAMPALÍK, Jan
The main present effort in the controlled fish reproduction is the finding universal preparation which are suitable for the ovulation induction of large fish species spectra. The preparation should not cause hight after-spawn mortality of generation fish and it is wantable to repeat inorganic spawn in following seasons too. The experiment which reviewed the tench fertility and condition with using several hormonal preparation was realized in working condition of Fishery Hluboká (hatchery Mydlovary) in 2006 {--} 2007. The gained generation material was separated in several intervals by weight and it was detected the working fertility in percent and semination in percent for individual weight categories. The experiment was realized by using following preparation: Ovopel, Dagin, Supergestran, Kobalerin.
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Vliv teploty na udržení schopnosti oplození a líhnivosti při přechovávání neoplozených jiker u lína obecného
ANDONIU, Andreas
This theses deals with the storage length of artificially spawn of hard roes of Tench (Tinca tinca) during different temperatures at the time before the semen discharging and activation to fertilization, hatching and consequent survival of fish hatchery throughout changeover from the embryonic to larval life period (beginning of active food intake). Homogeneous assortment of hard roes obtained from hormonally induced artificial hatching of 6 spawners has been used for this experiment. Samples of hard roes were put into plastic bowls and covered, immediately after artificial hatching. Subsequently, they were placed into tempered, thermo-isolating containers with temperatures of 5, 10, 15, 20, 25 and 30 °C. In time intervals of 0.5; 1; 1,5; 2; 3; 4; 6; 8 and 10 hours, a small amount of hard roes were taken away from each temperature (estimated 50 -100 pieces) and put into dry, glass beakers (in 3 repetitions in each temperature combination and length of storage). Subsequently, the semen discharging from 6 milters was carried out and activation by water was performed. Incubation took place in non-sticking environment. During the incubation, or more precisely during the consequent storage of embryos through temperatures between 19-20.5 °C, water was changed daily. Fertilization was evaluated 48 hours after fertilizing. Hatchery was determined 48 hours after beginning of hatching of first specimen. After changeover from embryonic to larval period of ontogenetic development, living food was offered to hatching fish (artemia sp.). Thereafter, the amount of hatched fish with filled intestines was counted. Ascertained values were depicted as a percentage from the total number of seeded hard roes as well as fertilized hard roes with the use of statistic methods (two factors Anovy with the repetition). The highest level (in statistic evaluation on the importance level alfa = 0.05) of hard roe hatchery was accomplished throughout the length of possession and temperature 1 hour/ 25 °C (68.0 +- 3.1 %). The high level of hatchery was maintained by hard roes stored for 2 hours, afterwards a gradual value decrease was registered. Similarly, that was achieved with hatching parameter, where the high level of hatching was achieved with hard roes possessed for the period of 3 hours (except temperature of 30 °C), afterwards the hatchery was decreased. Pursued survival and food intake parameters of hatched fish (from the practical point of view) confirmed above stated dispositions. The high hatchery from placed hard roes was maintained for 1.5 - 3 hours (except 30 °C), thereafter there was its gradual decrease. In the time of 8 hours (temperatures 5 - 20 °C), the survival of 1.2 +- 1.8 %, was found out, with the rest, the survival was nearly zero.
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Možnosti fixace vzorků pro měření obsahu DNA u ryb průtokovou cytometrií
HUBÁLEK, Martin
This thesis aims to assess the possibility of the usage of various biological fixatives for fish cell and tissues samples in order to extend its storage for later flow cytometric measurement of DNA content. The model species chosen were sterlet and tench, from which three types of samples were obtained: blood and fin tissue of subadult / adult individuals and tail tissue of hatched larvae. Altogether 13 fixation methods were tested for each type of sample of both model species. Methods were chosen based upon their easy feasibility and low time-consumption. The samples were measured on flow cytometer in native state immediately after sampling and placing in physiological saline and after 1, 5 and 10 days of fixation during which they were stored in a fridge or in a freezer at -80 ?C. Their analysis was carried out simultaneously with standards native cells from tench fin tissue when investigating sterlet samples, and commercially available fixed trout erythrocytes for tench samples. A fluorochrome used was 4',6-diamidine-2'-phenylindole dihydrochloride (DAPI; with excitation/emission maxima 358 / 461 nm). Based on the evaluation of coefficients of variation (CV) of fixed samples and the changes in their fluorescence levels in comparison with native state, optimal procedures for extended storage of all types of samples from both model species are suggested.
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Variability of lipid classes and fatty acid composition during over ripening of oocytes from tench (\kur{Tinca tinca})
KRZYŚKÓW, Anna
In this project, the eggs of tench (Tinca tinca) were used for the evaluation of changes in fatty acid (FA) composition and lipid classes during in vitro ova ageing until the occurrence of over-ripening. Stripped ova of 6 females were collected separately and stored in sterile cell culture plates in an incubator at 20 °C for up to 24 hours post stripping (HPS). Stored ova were fertilized at 0, 2, 4, 6, 8, 10 and 24 HPS. Egg eyeing and hatching rates were assessed as indices of egg quality. Upon fertilization at each HPS, samples were taken separately frozen in liquid nitrogen and stored at -80°C till further analyses. Differences in the FA and lipid composition and embryo survival rates at the different fertilization times post-stripping were evaluated. The lipid fraction was extracted from the oocytes according to Hara and Radin (1978). The lipid content of the samples was determined gravimetrically from total extracted lipid. The FA were then analysed with a gas chromatograph equipped with a flame ionisation detector and PVT injector. The peaks were identified by comparing their retention times with those of authentic standards. Major lipid classes and the phospholipid classes were separated according to (Olsen and Henderson, 1989). Quantitative analysis of the separated lipid- and phospholipid classes was done by scanning the plates after derivatisation with a CAMAG TLC Scanner 3 (Camag, Switzerland). Identification of the lipid classes was performed by comparison with authentic standards applied on the same plate. In present study no significant changes were observed in lipid content and composition during storage of eggs until over-ripening. As well FA composition did not change over time indicating another reason of deterioration of oocyte quality than the proposed lipid oxidation. However individual fishes in this study showed much different fertilization rates that corresponded with their levels of cholesterol and triacylglycerols in minor degree.
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Odkrm plůdku lína obecného (Tinca tinca) s využitím obohacených nauplií žábronožek (r. Artemia)
BOŇKO, Dominik
The aim of the experiment was investigate the the effect of feeding early Tench fry with enriched Artemia nauplii on the survival in the under laboratory conditions at an average water temperature of 25.8 °C. The total duration of the experiment was 42 days. We used two commercial enriching products of Selco company (Selco DHA and Selco Spresso). The fry were fed with this diet in two variants (7 and 21 days), followed by a transition to dry starter feed. In the experiment were also included control groups fed with unenriched nauplia (also for 7 and 21 days). The transition to starter feed (Inicio Plus GR from Biomar) was done after a four-day co-feeding, when the proportion of nauplia was gradually reduced. Groups fed with naplii for 7 days had a higher growth rate (13.41 %-d-1), an average individual weight (142.74 +- 57.06 mg) and a total length (21.08 +- 3.27 mm), including higher variability of the two last parameters. At the same time, low survival (2.8 %) was observed. Produced biomass was also lower. Fry fed with live feed for the first 21 days had lower growth rate (10.77 %-d-1), individual weights (48.61 +- 18.13 mg) and total length (16.05 +- 1.66 mm). Survival of fry was much higher (25.1 %) in this case. Produced biomass of the fry fed with live food for three weeks was almost three times higher (219.3 g) than biomass of the fry fed with live feed for one week (71.4 g). It can be observed that the influence of enriching of the artemia nauplii on the growth of the tench fry wasn´t proved. However, fry fed a week of enriched nauplii reached a slightly higher survival rate during the rearing period. Compared with the control group (3.3 %), the survival rate of the fry fed with live food enriched of Selco Spresso was 3.7 % . The survival of Selco DHA was 1.4%. Reached results could be partially influenced by parasitic disease of the fry during rearing.
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Performance testing of interline hybrids in tench.
HOMOLA, Ondřej
This thesis is focused on evaluation of performance traits as growth, survival and carcass yield in hybrids of chosen tench breeds. In this test were used hybrids of these breeds of tench: Vodňanské (V), Táborské (T), Maďarské (M) and Hlubocké (H), which served as maternal breed. As a control group the golden tench was used.
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Impact of nutrition and rearing technology on the changes of the quality of common tench (Tinca tinca) meat
PŘÍBORSKÝ, Josef
The aim of the study was to determine the impact of diet (natural and formulated feed) on the chemical composition and fatty acids profile of the harvested fish. The content of dry matter in fish flesh resulting from the formulated diet was higher vs. the natural diet (23.94?1.24 % vs. 19.66?0.82 %) with nitrogenous compounds (60.24?2.82 % vs. 72.12?1.75 %), total fat content (24.81?4.51 % vs. 6.14?2.85 %) and ash (7.55?1.28 % vs. 10.54?1.53 %) respectively. The spectrum of fatty acids was determined by gas chromatography using Varian 3800 equipment. Tench fed on a formulated diet in the recirculating system had a significantly higher content (P< 0.05) of monounsaturated fatty acid (MUFA = 43.04?1.68 %) and n-6 polyunsaturated fatty acids (PUFA = 15.47?1.07 %) in their flesh compared to the flesh of fish reared in earth ponds on a natural diet - MUFA (32?5.29 %) and n-6 PUFA (13.6?1.66 %). Tench fed on a natural diet in earth ponds proved to have a significantly higher content (P< 0.05) of n-3 PUFA (16.8?4.38 %) and ? PUFA (30.3 ? 5.3 %) than tench reared in the recirculating system - PUFA n-3 (10.05?0.85 %) and ? PUFA (25.52?1.07%). The ratio n-3/n-6 for fish from earth ponds was 1.2; for fish from the recirculating system the ratio was 0.65. The results show a significantly higher composition of n-3 PUFA in flesh of tench from earth pond with natural food compared to fish on an intensive feeding diet in the recirculating system which showed a higher content of n-6 PUFA.
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Comparison of growth and survival of selected tench breeds in performance test
PRCHAL, Martin
This thesis is focused on comparison of performance traits of growth and survival of selected breeds of the common tench using the pure-blooded animal breeding method. The best way how to compare performance traits of particular breeds is through so-called performance tests. For this thesis following breeds were chosen: Vodňanské -(V), Hlubocké(H), Königswartha (German - N), Mariansko-Lázeňské (ML) and Romanian(R). The Golden tench were chosen as a control breed in order to correct the influence of the environment on the weight achieved. The testing began with selection and stripping preparation of spawners of relevant breeds selected for testing. Own performance test of selected groups proceeded from yolk - sac fry to the age of L2 in ponds with semi-intensive farming. Each tested breed was bred in the first growing period and in winter period together with the control group only. After group marking (the second growing period) by the cryogenic method, all breeds were bred together with triplication. In the first testing period reproductive parameters of spawners and their weight and survival of tested breeds were evaluated, in other period only weight and survival were evaluated. Reproductive parameters in males did not vary statistically in none of the parameters using any statistical method. In females significant differences were proved only between the breeds ?Hluboká? and the control breed. After the second growing period the highest weight was achieved by the Mariánsko-Lázeňské breed (112.9 ? 44.9 g), whose weight was statistically comparable only with German breed (105.4 ? 32.4 g). The survival after this period ranged from 70,4 % (Romanian breed) to 84,1% (Mariánsko-Lázeňské breed) and all breeds had statistically comparable values. The best performance traits after the second year of testing was achieved by the Mariánsko-Lázeňské breed.
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