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Porovnání účinnosti peletovaného krmiva s obsahem hmyzu a směsi s běžným složením při odchovu okouna říčního (Perca fluviatilis) v poloprovozních podmínkách
NOVOTNÝ, Martin
This thesis deals with the possibility of using insects as a potential source of proteins in artificial feed for Eurasian perch. In conventional feed, 25 % of fish meal was replaced by meal from adult Acheta domestica and Zophobas morio. There were performed two 12-week long experiments, the first one in the Experimental Fishery Workplace at the Faculty of Fisheries and Water Protection of the University of South Bohemia in Vodňany and the second one in the commercial operation of Anapartners s.r.o. Company in Prague Horní Počernice. The production indicators of the breed were evaluated and the fat and fatty acids in the fish muscles were analyzed as an important indicator of its nutritional value. At the end of both experiments, fish fed by experimental feeds showed lower length and weight gains and worse feed conversion, compared to fish fed by control diet. During the experiment and after its completion, the feed effect on fish survival were not noticed. Furthermore, there were not found any changes in fat content in fish muscles, but changes in the content of individual fatty acids were noticed. In fish fed with experimental feed, the content of linoleic acid (C18: 2n-6) increased as well as the total content of n-6 fatty acids, on the contrary, the content of n-3 fatty acids in the fish muscle decreased more than in fish fed by control diet. This also affected the resulting ratio of the n-6 fatty acid to n-3 fatty acid ratio, while this ratio increased significantly in the experimental fish group. Changes in fatty acids content in fish muscle were small and did not affect its nutritional value from the perspective of human consumption. In other experiments dealing with this topic, it is necessary to focus on testing of other insect species or to modify the quantity of substituted fishmeal.
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Vliv kvality a zpracování siláží a senáží na mléčnou užitkovost dojnic ve vazném ustájení
VŠETEČKA, Miroslav
Milk yield of dairy cows is mainly determined by their nutrition and state of health. Dairy cows turn roughage into milk the most effectively. The assessment of the level of nutrition and the processing of silage and haylage was performed in operating conditions. Quality of roughage, technique of nutrition and its influence on milk yield in stanchion-tied stable were assessed. Data were observed over a peri-od of 3 years (2012 2015). The observation included Czech Fleckvieh Breed and Holstein Breed. Average daily yield data were monitored with all dairy cows, which were in lactation period during the observation. The gained data were entered into diagrams and charts and evaluated. The highest performance results have been achieved in 2015, the lowest performance results have been achieved in 2013.
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Cemical composition of hemp (\kur{Cannabis sativa}) and possibilities of its utilization as animal feed
NĚMCOVÁ, Michaela
Cannabis sativa L. is an annual cultural plant used from ancient times up to the present in many spheres of the human life. The aim of this bachelor study was to summarize on the basis of literature sources the information about chemical composition of the hemp seed (basic composition, content of amino acids, fiber, vitamins and specific substances, etc.), genetic variability in the substances content, and possibilities of utilization of the hemp seed and also plant residues as feed. Feeding hemp seeds to poultry increases egg production and enriches egg yolk with carotenoids, - 3 and - 6 fatty acids and decreases the cholesterol content. In case of broilers, hemp seeds increases the weight of the breasts, thighs, liver, stomach, intestines and the portion of abdominal fat. Hemp seed cakes have a positive effect on rumen function, support reception of neutral detergent fiber and increases the unsaturated fatty acids content in the meat. Hemp oil relieves stress and improves immunity of the fed animals.
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Optimization of production steering shaft
Hlavinka, Martin ; Kalivoda, Milan (referee) ; Jaroš, Aleš (advisor)
Bachelor thesis deals with the creation of the optimal divided chip in the turning technology. The material for production of the steering shaft is steel C35RC suitable for forming and turning from which semi-finished products are produced at horizontally forming presses. They are machined at the production robotized line where the problem with the undivided chip arises. For the specified set of cutting conditions the uses the cutting tools which aren’t very suitable for the given types of technological operations. The recommended values of cutting conditions are different from the specified set of cutting conditions. The result will be choice of new-cutting tools for turning technological operations to shape short divided chip.
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Application of Mass Spectrometry for the Determination of Oxidative Stress Markers and Mycotoxins
Čumová, Martina ; Večeřa, Zbyněk (referee) ; Hajšlová, Jana (referee) ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
The first topic presented in the dissertation thesis is determination of isoprostanes as markers of oxidative stress and other compounds affected by presence of oxidative stress. Isoprostanes iPF2-III, iPF2-VI, iPF2-VI, astaxanthin and polyunsaturated fatty acids (PUFA), especially arachidonic acid (AA) were monitored in Atlantic salmon eggs (Salmo salar). Methods for the determination of these compounds have been developed and optimized using chromatographic separation coupled to conventional or mass spectrometric detection. Freshly laid eggs, eyed embryos and non-viable eggs were used to test a general hypothesis that egg viability can be affected by susceptibility to oxidative stress, either through the specific fatty acid concentration and/or the antioxidant capacity of the eggs. Levels of isoprostanes and arachidonic acid (AA) were significantly higher in non-viable eggs than in control (eyed embryos) as well as relative abundance of PUFA. While no difference of isoprostanes was found between freshly laid and control those from the Atlantic stock except iPF2-VI which was observed under the LOQ in the control. Higher levels of PUFA and AA in comparison with the control were observed in the freshly laid eggs. However, the only statistically significant difference was observed in the amount of astaxanthin. Different levels of PUFA and astaxanthin may be related to their biochemical consumption during the development of eggs. This work evaluated potential effect on the viability of eggs Salmo salar due to the presence of oxidative stress. The monitoring of mycotoxins in food and feed was the subject of the second topic. Mycotoxins are secondary metabolites produced by fungi. They are ubiquitous undesirable natural contaminants that are toxic for humans and animals. Today are known more than 500 mycotoxins. However, only few of them are regulated by the European Union. The European Food Safety Authority (EFSA) was asked by the European Commission to provide a scientific opinion on other mycotoxins for which statutory limits could be developed. In this study is proposed simultaneous screening allowing fast, reliable and sensitive approach, identification and quantification of 17 mycotoxins in food and feed sample. The method includes both mycotoxins regulated by the EU and selected mycotoxins required by the EFSA (aflatoxins, deoxynivalenol, nivalenol, zearalenone, fumonisin, ochratoxin A, T-2 toxin, HT-2 toxin, enniatins and beauvericin). Analytes are isolated by the modified QuEChERS method. For separation and target mycotoxins detection, ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC –MS/MS) was employed. The method also allows determination of ergot alkaloids (ergocornine, ergosine, ergocryptine, ergocristine and their respective epimers). The developed method was used either for monitoring mycotoxins and ergot alkaloids in feed and raw materials and barley and malt prepared from it.
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On The Analyse of High Productive Reaming Technology
Gashkova, Irina ; Slaný, Martin (referee) ; Píška, Miroslav (advisor)
Diplomová práce se zabývá analýzou technologie vysoceproduktivního vystružování. V rámci práce byly provedeny testy vystružování za různých technologických podmínek (vc=40, 60, 80, 100 m/min; f=0.2, 0.4, 0.6, 0.8 mm) na materiálu austenitické oceli DIN 1.4404 při použití vystružovací hlavicí MT3. Jednotlivé operace vystružování byly porovnány z hlediska parametrů jako tlačná síla, krouticí moment, výsledná drsnost obrobeného povrchu a dále z hlediska tvaru třísky. Následně byly vypočítány průměrné hodnoty a směrodatná odchylka naměřených parametrů. Dále bylo provedeno porovnání pomocí diagramů. Výsledky ukazují lepší kvalitu, nižší drsnost povrchu (Ra 0,37 µm) a méně zdeformovanou třísku při pomalejších řezných rychlostech (40 m/min) a menším posuvu na otáčku (0,2 mm). Výsledky také ukazují nárůst tlačné síly a krouticího momentu za uvedených technologických podmínek. Při zvyšující se řezné rychlosti vystružování tyto silové účinky klesají.
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Determination of selected perfluoroalkyl compounds in complex matrices
Ondreášová, Klára ; Vávrová, Milada (referee) ; Mgr. Petra Kosubová, Ph.D (advisor)
Diploma work focuses on the determination of selected representatives of perfluoroalkyl substances in complex matrices, particularly, in sewage sludge and feed. In case of sewage sludge, samples were extracted into methanol and three extractions techniques were compared: accelerated Soxhlet, pressurized liquid extraction and Powley method. Powley method showed sufficient efficiency, the lowest matrix effect and minimal background. Perfluorooctane sulfonate was present in all tested samples of sewage sludge (0.74–38.02 ng.g-1). Other detected compounds were perfluorodecanoic acid and perfluorooctanoic acid. Three extraction techniques were tested on feed samples (QuEChERS, fast methanol extraction and Powley method into acetonitrile). Powley method provided the cleanest extracts and showed simultaneously the highest recovery of native perfluoroalkyl substances and the lowest matrix effects. Perfluorooctane sulfonate and perfluorooctanoic acid were rarely present in samples of complete and supplemental feeds, while other perfluoroalkyl substances were found at levels below limit of quantification or they were not detected at all. Perfluorooctane sulfonate (0.100–2.768 ng.g-1), perfluoroundecanoic acid and perfluorotridecanoic acid were determined in all fish meal samples.
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Milling Machine for Machining of Plastics
Frejlich, Tomáš ; Brada, Michal (referee) ; Brandejs, Jan (advisor)
Bachelor thesis deals with the structural design of the longitudinal and transverse feed for the milling of embedded hollow fibers of fixed size used in heat exchangers and the design of these components during milling. The work contains a brief description of the routing, basic milling division and a brief overview of the kinds of lines that are use for machine tools. It als presents an overview of fastenings for easy and quick clamping of milling, individual design variations and optimal solution. The works also includes the drawing of the components and complete set. The results of the Bachelor thesis are used for the Laboratory heat transfer and flow at University of Technology, Faculty of Mechanical Engineering.
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Friction and air feeders for paper sheets
Svoboda, Ondřej ; Košťál, David (referee) ; Brandejs, Jan (advisor)
The thesis is focused on summarizing the evidence on the issue of paper sheets feeding at the final processing of documents. The thesis includes dividing of paper feeders, their characterization, and description of friction and air feeders, which are most widespread. As a model for the description methods of sheets feeding were used machinery CFM 700 and GPM 540A of Cyklos company. The thesis also compares friction and air feeding from the constructional point of view. The conclusion focuses on the new methods in the paper feeding in future.
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