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Influence of sperm density on outcomes of cryopreservation in carp
STECHKINA, Taisiya
The current work is devoted to the study of the influence of common carp (Cyprinus carpio) sperm concentration during freezing on cryopreservation outcomes. During the experiments, seven concentrations of sperm were used. Two different approaches of sperm dilution (using seminal plasma or cryoprotective medium) were tested to directly determine the impact of cell concentration in solutions and simultaneously to test an additional positive effect of seminal plasma presence during cryopreservation on sperm cryoresistance. This study confirmed the assumption that, due to close cell-to-cell interactions, more concentrated samples after thawing account for a smaller percentage of living cells than low-concentrated samples, while different densities didn't significantly affect other motility parameters of sperm, except velocity. However, the low motility is compensated in the case of using concentrated sperm by the initially large number of spermatozoa in these samples, and the sperm content in such samples is sufficient for successful fertilization, especially when using a high sperm per egg ratio during the fertilization process. In this case, a lower volume of sperm is required in comparison to low-concentrated samples, which is beneficial in terms of saving cryostorage space, chemicals, and work. Therefore, from the considerations of optimization, the use of highly concentrated sperm samples can be offered. As a part of this work, an elaboration of the spectrophotometry method for the estimation of common carp sperm concentration was carried out. A strong correlation was obtained between absorbance and sperm concentration calculated using the Bürker counting chamber, and an equation of this relation was deduced. The results confirm the possibility of using this method as an alternative to the widely used method of counting sperm concentration with a haemocytometer, however, some further improvements of the method remain possible.
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VÝVOJ NOVÝCH RYBÍCH PRODUKTŮ PRO PŘEDŠKOLNÍ DĚTI
KALICOVOVÁ, Veronika
The aim of the diploma thesis was to develop newly innovative fish products. The intention is to increase fish consumption through new developed innovative fish products and proposed recipes. Fish supply healthy polyunsaturated fatty acids (PUFAs) and highly unsaturated fatty acids (HUFAs) to the human body, including eicosapentaenoic (EPA) and docosahexaenoic acid (DHA), which are essential for the proper development of the human organism. 11 new products and 13 new recipes were developed, which were subsequently sensory evaluated by the main target group of consumers. Preschool children were chosen as the target group of consumers, because their consuming habits are established in this life period. The new fish products have met all legislative standards and limits of food safety. Nine products were positively evaluated by the target group. Five products were selected for further analyses (fish balls, fish burgers, fish ham, fish mistura, fish sausages). The issue was theoretically studied according to worldwide research studies. In practice, the project was implemented with coordinated comprehensive cooperation with nutritionists, fish product technologists, but also with preschool facility employees, children and their families. The output of this work are new fish products which are available on the market. Fish products were made from the muscle of African catfish (Clarias gariepinus). The market offer of nutritionally high-quality foods which have a positive impact on human health has been increased. At the same, time several recipes from the African catfish (Clarias gariepinus), the common carp (Cyprinus carpio) and the rainbow trout (Oncorhynchus mykiss) have been proposed as a guide for easy preparation of healthy dishes.
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Comparison proportion of Cyprinus carpio according to scale
ŠIKOVÁ, Jana
The aim of the study was to compare the yield of scaly carp and mirror carp, two major representatives of the common carp (Cyprinus carpio), predominantly bred in the Czech Republic. The yield comparisons were performed in a newly created company store, where it was important to assess the suitability of fish for different products. A partial objective was, through a questionnaire survey, to determine the popularity and frequency of the consumption of carp. Finally, the intensity of individual forms of carp was monitored. The experiment was conducted in the years 2012-2013 during the four seasons spring, summer, autumn and after relaying. The evaluation took place for two types of carp, the mirror carp and the scaly carp. Another reference subject was two ponds, the naturally fed Vrbský Pond and the feeding pond Musik. Both carp are characterized by distinct developmental and life cycles. The mirror carp, the body structure of which is smaller than the scaly carp, demonstrated a higher yield in all monitored aspects at the end of the evaluation. At the same time, the fillet yield of both representatives achieved similar values and ranged from about 43-48%. The carp from the feeding pond Musik gave a surprising result, where a lower yield was expected due to the lower amount of plankton and zoobenthos, a natural food for fish. During the monitored period, the highest yield was recorded in the period after relaying, while the lowest yield in the spring, due to the selected increased fish stock for the given year.
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Test of medicaments perspective for exploitment at the fishing profession
SCHEINER, Pavel
The aim of the study was to assess the effects of orally applied praziquantel on the treatment efficacy against most abundant tapeworms (Atractolytocestus huronensis Anthony, 1958 and Khawia sinensis Hsü, 1935) of common carp (Cyprinus carpio Linnaeus). Naturally infected fish (one-year-old; K1+) were divided into 3 trial groups containing 17 specimens and administered with praziquantel mixed in heat-treated amyloid vehicle (in doses of 50 mg.kg-1 body weight). In 3 groups of control, the fish were administered amyloid vehicle only. Fish were examined by using of gut dissection 2, 4 and 6 days after administration. At 48 hours post-treatment, significantly lower prevalence of both parasites was found. The invasion of A.huronensis was fully eliminated in all fish after 96 hours whereas some specimens of K.sinensis still persisted in the gut of few fish. The full elimination of both parasites was observed 6 days after administration. Our results showed that elimination of K. sinensis takes longer than elimination of A.huronensis. The dose of 50 mg kg-1 of orally applied praziquantel is effectual to control A.huronensis and K sinensis infections in common carp successfully. The effect of oral applied praziquantel on the hematology and biochemical parameters blood of common carp (Cyprinus carpio L.), infected by the tapeworms Atractolytocestus huronensis and Khawia sinensis was the object of analyse. It was the partial goal of the work. The infected fishes were divided to the six groups. The praziquantel was applied stirred in amyloid vehicle in dose 30 mg/kg of quick materiality for two groups and for two to other groups in dose 50mg/kg of quick materiality. Only clean amyloid vehiculum was applied to two control groups. Blood taking and resulting patoanatomic investigation was effected 24 and 96 hours after application of praziquantel. Results of hematology investigation of blood obtained 24 hours after the application point on significant fall (p< 0,01) of the number of erythrocytes, hemoglobin and hematocrit in both groups E1 and E3, which achieved the original surface after 96 hours. The significant upsurge (p<0,05) of the surface serum hepatic enzyme ALT was recorded after 96 hours.
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Food competition between common carp (Cyprinus carpio) and topmouth gudgeon (Pseudorasbora parva)
NĚMEC, Karel
Small cyprinid fish, the topmouth gudgeon (Pseudorasbora parva Schlegel, 1842) is considered as an undesirable fish species because it represents an important food competitor for commercial non-predatory fishes. This study was performed under pond conditions (four ponds in South Moravia and two ponds in South Bohemia) during the growing seasons in 2006 {--} 2007. The purpose of my work was to determinate the level of food competition between topmouth gudgeon and common carp (Cyprinus carpio) as a dominating pond fish species. Food selectivity was evaluated using Ivlev´s electivity index (Jacobs, 1974). The level of food competition between common carp and topmouth gudgeon was used to evaluate the index of food similarity according to Shorygin (1952). The diet of topmouth gudgeon consisted mainly of chironomid larvae and zooplankton, mostly cladocerans (Daphnia, Bosmina), detritus and periphyton (Oscillatoria, Scenedesmus, Sphaerotilus). Macrophytes, copepods and Brachionus were also ingested by P.parva but in comparatively low proportions. In contrast, carp diet consisted mainly of bottom items including chironomid larvae, macrophytes and organic debris, mainly detritus and periphyton. The food items of lesser importance were dragon fly (Anisoptera) larvae, cladocerans (Bosmina, Daphnia) and ostracods. Topmouth gudgeon competed with common carp for chironomid larvae, periphyton and detritus, for zooplankton (mainly cladocerans Daphnia, Bosmina). The highest valuation the food competition was registered in fish from the Vracovický pond (South Moravia) and the Podsedek pond (South Bohemia), when it amounted from 24.02 to 34.78 % food similarity.
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