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Vliv vykrvení na kvalitu masa kapra obecného (Cyprinus carpio)
KUBÍK, Michal
The aim of this study was to test the influence of bleeding on the flesh quality of common carp. For the assessment of the influence of bleeding on the colour, spectrophotometrical measuring was used. The sensory quality was evaluated to an ISO 8529 standard by a trained staff member of the Institute of Aquaculture and Protection of Water. Both raw and cooked samples were evaluated. Microbiological analysis was done according to ISO 4833 standard and lipid oxidation measured by TBARS. The influence of the bleeding was observed in all colour parameters (L*, a* and b*). The average of L* values was 43.7 +- 1; 42.7 +- 1, a 43 +- 0.9 in bled group and 37.51 +- 0.54; 37.98 +- 0.79; 37.42 +- 0.6 in unbled. The average of a* values was -1.4 +- 0.2; -1.6 +- 0.2; -0.9 +- 0.4 in the bled group and 4.5 +- 2.3; 3.6 +- 1.6; 7.4 +- 1 in the unbled group. A significant difference (p < 0.05) between groups was observed in all days of study in the L* and a* parameter. In the b* parameter there was a difference observed just in the first nine days. A significant difference (p < 0.05) between the bled and the unbled groups was observed in all criteria on the raw sample on the 1st and 3rd days. Cooked samples were significantly different (p < 0.05) just on the 6th day of study. Microbiological results came up to 4 +- 0.2 log CFU.g-1 in the bled group and 6.3 +- 0.1 log CFU.g-1 in the unbled group. The influence of bleeding was shown in lipid oxidation too. At the end of the study TBARS values were 17.8 +- 8.8 ug.kg-1 of the sample in the bled group and 39.9 +- 6.4 ug.kg-1 of the sample in the unbled group. In both groups, exponential growth was shown. The influence of bleeding was observed in all parameters. It can be stated that the bleeding has a positive influence on the flesh quality of common carp. In order to convert these results into practice, further studies to optimize the bleeding process are needed.
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Lokalizace a kvantifikace rybomorky \kur{Sphaerospora molnari} (Myxozoa) u kapra obecného
LISNEROVÁ, Martina
The thesis deals with localization and quantification of Sphaerospora molnari (Myxozoa) in common carp (Cyprinus carpio). Sphaerospora molnari is microscopic endoparasite which attacks various tissues and organs, preferentially parasitizing intracellularly (histozoic type) in a carp fry. In this work, we studied the course of parasite infection in the various tissues and organs of the host (blood, gills, skin, kidney, liver, and muscle) in laboratory conditions. The course of infection was detected using qPCR.
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The dynamics of anglers' attendance and exploitation of carp in the Hostivař Reservoir directly after stocking and out of this period
Winterová, Michaela ; Jankovský, Martin (advisor) ; Čech, Martin (referee)
The main hypothesis supposes a different angler behavior directly after stocking and out of this period. The aim of this work was to evaluate carp preference according to time (within one day in one district) and place (choice of the locations) variability. As an explanatory parameter the number of environmental factors was tested such as weather, the type of a bait or the sensitivity of fishing technique. This information was surveyed by interviewing the anglers at the Hostivař reservoir. The survey took place in two periods - in autumn 2008 after stocking and comparing period in spring 2009. Data elaboration was taken with CANOCO statistic ver. 4.5 software, when the factors influencing frequency of fish species were searched for. Significantly tested were the factors of bread bait, increasing volume of fishing line and amount of anglers proving the concern of that group for orientation of carp catch. From the following results was obtained the average time spent by the anglers at Hostivar - approximately 5 hours. The average visit rate in autumn was 39.2 angler/day and in spring 34.1 angler/day. The analyses of fishing location show the popularity of places with easy entrance to the bank and the better carp catch in those places. The anglers' efforts were in autumn 2002.7 hours/ha/year and in...
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Modelling HSRP and GLBP Gateway Redundancy Protocols
Holuša, Jan ; Marek, Marcel (referee) ; Veselý, Vladimír (advisor)
This thesis deals with theoretical analysis of First Hop Redundancy Protocols. It describes Hot Standby Router Protocol, Virtual Router Redundancy Protocol and Gateway Load Balancing Protocol. It also shows examples of configuration of each protocol on Cisco devices with supported version of the Cisco IOS. Furthermore, this thesis includes design of two of these protocols, Hot Standby Router Protocol and Gateway Load Balancing Protocol, and their implementation in discrete event simulator OMNeT++ and Automated Network Simulation and Analysis library. Finally, the thesis presents results of testing of the implementations in comparison with actual Cisco devices.
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Capacitated Arc Routing Problem
Franc, Zdeněk ; Pelikán, Jan (advisor) ; Fesenko, Anastasiya (referee)
The Capacitated Arc Routing Problem has many applications in real life. The aim of this problem is to minimize the total cost at fulfilment of the requirements of arcs. The Capacitated Arc Routing Problem is an extension of the Chinese Postman Problem, which is a special type of the Vehicle Routing Problems. In this thesis is explained the issue of the Chinese Postman Problem and its extensions at first. Subsequently the applications of mathematical models are illustrated on a model example. However these mathematical models, which are searching the optimal solution, do not use so much in reality. Therefore the randomized heuristic algorithm for solving these problems is suggested and programmed in this thesis. Subsequently this heuristic was applied to case study of garbage collection in Podebrady city.
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The formation of biogenic amines in flesh of selected fish species
MATĚJKOVÁ, Kateřina
The thesis deals with the use and effectiveness of some less common methods of conservation of fish meat. The formation of biogenic amines in meat is observed in connection with the non-traditional preservative methods. Amines can serve as indicators of protein degradation. The quality of fish was considered in connection with the increasing content of selected biogenic amines (putrescine, cadaverine, spermidine, spermine, 2-fenylathylamine, histamine, tyramine and tryptamine). Ultra performance liquid chromatography (UPLC) was used as the method for determination of biogenic amines. Amines were derivatized by dansylchloride before their UPLC separation. The fish flesh was vacuum-packed. Samples were stored for several weeks in a thermostat at the selected storage temperature after the application of selected preservative technique. Beta-irradiation and high hydrostatic pressure were used for the preservation of fish flesh. Control samples were not exposed to the â-irradiation and high pressure. The organoleptic properties were studied for all samples (smell/odor, insight and shape). Beta-irradiation was applied to fish meat of common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss). Both these species of freshwater fish are economically significant. Carp and trout are the species being mostly consumed in the Czech Republic. Fish meat is considered to be provided the flesh is fresh. A testing series of samples was created with common carp to determine the appropriate dose of â-irradiation. The maximum permissible dose of irradiation for fish meat is 3 kGy. Fish samples were exposed this dose in the first experiment. The dose of irradiation was reduced in following experiments based on the experience from the initial experiment. The doses of 0.25, 0.5, 0.75, 1.0 and 2.0 kGy were applied to rainbow trout. The value of 0.75 kGy of â-irradiation or higher (1.0, 2.0 and 3.0 kGy) prolonged the shelf life of fish meat, which was stored for three months (98 days). Prolonging of the shelf life of fish meat to approximately 98 days at 3.5 °C is redundant from technical point of view. For that reason lower doses 0.25, 0.5 and 0.75 kGy were tested in more detail in the repeated experiment with carp meat. Lower doses of â-irradiation are considered to be more acceptable and-at the same time-sufficiently effective for delaying the beginning of degradation processes. 6 High hydrostatic pressure was applied to meat of common carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss) and pike (Exos lucius). Pike is another very popular kind of freshwater fish. Pike flesh is very tasty, but in spite of this, pike is not so much popular among consumers compared to carp and trout. The cause is its high price. Samples of pike were stored at standard temperature 3.5 °C and also at higher temperature 12 °C (unlike experiments with â-irradiation). Lower temperature of storage (3.5 °C) followed the conditions of storing of fish meat in industrial refrigeration facilities and households. The high pressure might not be sufficient for preservation at higher storage temperatures. This assumption was based on available information. Samples were treated by high pressure and stored at both 3.5 °C and 12 °C to verify this assumption. Higher temperature simulated either failure of refrigeration equipment or unsuitable store temperature of meat. In all species selected freshwater fish two levels of high pressure were applied ? 300 and 500 MPa. Both levels had significantly reduced the formation of biogenic amines, especially in samples stored at 3.5 °C. At this temperature, the effect of 300 and 500 MPa delayed start of degradation processes in fish meat by 3?4 weeks. At 12 °C and 500 MPa, high pressure extended the sustainability of meat by no more than one week. 500 MPa is effective treatment at the lower temperature of 3.5 °C. High pressure is not reliable preservative techniques at higher temperature.
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The Demembranation as a Tool to Study a Movement and Physiology of Activation of Fish Spermatozoa
BLAŽKOVÁ, Jaroslava
The aim of the thesis was the summarization of information about the demembranation method as a means of study of the physiology of activation and motility of fish spermatozoa. A simple demonstration of the method is also presented. The demembranation of fish sperm is a method, in which cytoplasmic membrane (the phospholipid bilayer, which separate intercellular and extracellular environments) is destroyed. A mild non-ionic detergent, TrintonX-100, was used in the study. Common carp (Cyprinus carpio) as a representative member of Teleost fish and sterlet as a member of Chondrostean (elasmobranch) fish were studied in the thesis.
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Damages caused by predation of invertebrates on the earliest development stages of fish
LOŽEK, Filip
Cílem bakalářské práce bude zjistit do jaké míry je přítomnost bezobratlých predátorů pro raná stádia ryb nebezpečná a má vliv na míru jejich přežívání. Většina hospodářsky chovaných druhů ryb se do rybníků nasazuje ve stádiu váčkového plůdku a nedochází k předchozímu rozkrmování na vacích či jiných odchovných zařízeních s pozdějším vysazením již silnějšího rozkrmeného plůdku. V prvních dnech po nasazení dochází také k největším ztrátám, které mohou být způsobeny ať už nedostatečnou potravní nabídkou nebo zejména predací bezobratlými predátory. Mezi ně mohou patřit tzv. "dravé" buchanky, larvy vážek nebo vodních brouků, a i některé druhy vodních ploštic. Student v průběhu bakalářské práce uskuteční několik laboratorních pokusů na rozplavaném plůdku kaprovitých, případně i okounovitých ryb, které bude konfrontovat s dravci, tedy dravými larvami hmyzu, vodními plošticemi či buchankami. Na základě pokusů vyhodnotí potenciální nebezpečnost jednotlivých dravců vzhledem k plůdku ryb.
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Evaluation of carp fish-scale reading production indicators in fishponds
PETR, Miloš
The main fish in the Czech pond aquacultures is Cyprinus carpio (common carp). All forms of carp feed on natural food and additionally they are fed with bread cereals. In the literary review I will describe the various cereals, which are used in carp-scale reading. Further I'll try to focus on the editing posibilities of the various cereals to increase their productive effectivity. In the chapter "Results and discussion" I will describe the characteristics of growth and condition indicators of experimental fish stocks during the growing season, in experimental ponds in South Bohemia, near the city of Třeboň. Finally, I review the results and try to propose some ways to use different feeds in working practices.
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The Occurrence and Basic Aspects of the Biology of Pseudorasbora parva (Temminck et Schlegel, 1842) in a Model Pond System located in the region of Třeboňsko
ČECH, Miroslav
The stone moroco (Pseudorasbora parva) is a invasive little fish whose species origin is not from our waters. It is desirable to eradicate this species from the Czech environment or at least decrease its numbers as much as possible, using an environmental method. The data for the dissertation was found out on a model pond system in Třeboňsko. This complex consists of thirteen ponds 203.1-hectare. The ponds in this locality are highly productive and their average depth is about one meter. The aim of the dissertation was to determine the composition of feed of Pseudorasbora parva and according to this, to assess the potential importance of this species as a rival to the locally bred carp (Cyprinus carpio). The other submission was to map the migration of Pseudorasbora parva in the aforementioned pond system and to determine what part of the pond is the most coveted by this fish and estimate the total number of fish population in some ponds. The use of fingerling nets was one of the methods used to catch Pseudorasbora parva in the shallow water of the ponds. Furthermore fish-pots were used for catching fish in the deeper parts, and drop nets were used for catching in the effluents. The Pseudorasbora parva was present for a whole calendar year in all parts of the system i.e. in all ponds, drains and in their effluents. The stone moroco occurred predominantly at the banks of the pond. The occurrence of fish in the open water was recorded sporadically. The sampling of plankton was carried out with plankton net in different seasons. With exception of winter when plankton was not found, the composition of feed the same during the whole year. Only proportional representation of species of plankton was different. The catching of Pseudorasbora parva was performed in the ponds Pražský, Rod, Láska and Víra, the fish was necropsied for assessment the intestine content. At the same time four carps of age group K2 were necropsied. By the analysis of the intestine content the conformity in the feed consummation by both aforementioned fish species was confirmed.
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