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Determination of the risk elements and other elements concentration in animal feed
Křehlíková, Jana ; Juglová, Zuzana (referee) ; Diviš, Pavel (advisor)
This thesis deals with the determination of selected microelements and macroelements and risk elements in dog and cat food. The theoretical part describes the nutrition of dogs and cats and focuses on the safety of the food in the context of contamination with risk elements. Another topic discussed is the chemical analysis of feeds, specifically the determination of nutritionally important substances, beneficial elements, and contaminants. The experimental part deals with the preparation and digestion of feed samples and the subsequent analysis of these samples using ICP-OES and AAS methods. The detected concentrations of the elements of interest in the feeds were compared with the feed standards issued by the Department of Veterinary Medicine and the decree issued by the Ministry of Agriculture. The analysed feeds were found to be deficient in some elements. The content of the risk elements in the feed met the legal limits and did not pose a health risk to the animal. Elements for which the legislation does not provide a maximum permissible limit were present in the feed-in in high concentrations that could already harm the animal's health.
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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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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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Management výroby kvalitního sena
Filipi, Eduard
This bachelor's thesis describes in the first part the influence of feeding high-quality hay on the productivity and health status of livestock. It is not surprising that high-quality hay is a suitable component of animal feed, and its use can have interesting economic results for the farm, as it has a positive effect on the production properties and health of animals. In the next part of the thesis, the history of hay production is described, taking into account the current state of hay production in the Czech Republic. The main part introduces factors influencing the resulting quality of hay and the technological process of producing high-quality hay. The following chapters describe the advantages and disadvantages of preservatives used during the harvest of hay with higher moisture content. Special attention is paid to methods of drying hay with cold and heat-treated air in haylofts. Finally, an experiment is proposed and described that compares three samples of hay with different chemical treatments.
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Hodnocení mikrobiologických rizik jedlého hmyzu
Hedvičáková, Adéla
Eating edible insects is an activity that has recently become increasingly important. In order to use edible insects safely, it is necessary to carry out, among other things, an assessment of the risks associated with consumption. This work focused on the microbiological risk assessment of edible insects. The theoretical part of the thesis provides information on the nutritional properties of edible insects and the risks associated with insect consumption. It also mentions legislation related to the inclusion of insects in food. The thesis describes the impact of insects and their consumption on the environment and presents factors that need to be further addressed in the future. The thesis provides a list of important pathogenic microorganisms. In the practical part it is possible to find a statistical evaluation of the measured values of the pathogens present in the insects and in the feed. Total counts of microorganisms, Escherichia coli, Enterobacteriaceae, moulds, Staphylococcus aureus and lactic acid bacteria were determined. The results were compared with those of studies on similar topics.
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Výživa vysokoprodukčních dojnic v podmínkách farmy na Písecku
Molková, Tereza
The main theme of this bachelor's thesis is the evaluation of the quality and level of nutrition high production dairy cows. This final work is separated into two parts. A literature search is prepared for the given topic, in which the nutrition of individual categories of dairy cows is specified in more detail and topics related to this are cove-red. The literal reshuffle follows an appreciation of the feed base in the practical part. two feed rations applied by a particular holding from the point of view of the nutrient content are analyzed and compared with calculated feeding standards for monitored dairy cow categories. The conclusion of the work is to assess the suitability of the feed ratio of each breed category.
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Výživa březích klisen
Strnadíková, Veronika
The bachelor thesis deals with the issue of nutrition of pregnant mares and is processed in the form of a literature search. At the beginning of the thesis there is an introduction to the subject, which is devoted to the characteristics of the equine sexual cycle and foaling. The aspects that influence them are described, as well as the reproductive and digestive organs, the development of the foal in the mother’s body and a description of the body score condition of the horse. Subsequently, two chapters are focused to the nutritional requirements of mares in early and late foaling and the differences between them. The last chapter describes specific types of feeds and their suitability for broodmares. Selected complete feed mixtures – granules and mueslis – are also summarised, with a description of their composition, recommended dosage and in tables is shown the content of the most important essential nutrients – digestible energy, starch, nitrogenous substances, fat, fibre, calcium, phosphorus, vitamins A and E and lysine.
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Design of Automatic Pet Feeder
Vlčková, Barbora ; Buganská, Tamara (referee) ; Rubínová, Dana (advisor)
This bachelor‘s thesis deals with the design of an automatic pet feeder that allows remote feeding support for cats and small to medium-sized dogs. The design is based on knowledge gained from design and technical analyses. Focus was placed on functional, ergonomic, and hygienic aspects. The resulting product is a modern pet feeder with added features that ensure the user has full control over feeding their pet.
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Content of risk elements in food for dogs and cats
Hrabalová, Karolína ; Slavíková, Zuzana (referee) ; Diviš, Pavel (advisor)
This bachelor's thesis deals with the determination of risk elements, namely mercury, arsenic, cadmium and lead in dog and cat food. The concentration of mercury was determined using the AAS technique, and the concentration of arsenic, cadmium and lead was determined by the ICP-MS method after microwave decomposition of the samples using mineral acids. A total of 30 feed samples were analyzed. In most samples, the concentrations of monitored elements were lower than the maximum permissible values given by the EU Commission Regulation, two samples did not meet the requirements of the regulation. The concentration of risk elements in the feed, except for arsenic, did not depend on the type of meat used in the feed. Feeds containing fish meat showed demonstrably higher concentrations of arsenic than feeds with other meats. Due to the relatively low proportion of meat in feed and due to the overall lower concentrations of risk elements in meat, it can be assumed that the vegetable or other component of the feed, or the technology of feed production, is responsible for the increased concentration of risk elements in feed.
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Potřeba dusíkatých látek ve výživě koní
Červínová, Monika
The bachelor thesis is focused on nitrogenous substances in horse nutrition. The work is divided into two parts, which intertwine. The first part concerns the digestion of horses, the importance of protein and non-protein nitrogenous substances and their effect on the horse's body. The specific requirements of nitrogenous substances for different categories of horses are also mentioned here. Part of the work is a summary of feeds, which also lists special protein feeds, which include, for example, spirulina, coconut flour or hemp seeds. The work also discusses possible problems with increased or decreased intake of nitrogenous substances. The second part contains my own work, the purpose was to monitor and evaluate the daily intake of nitrogenous substances in older horses who have a calm regime. For evaluation, samples of fed feed were taken and subjected to chemical analysis under the prescribed conditions to determine the nutrients contained. The results from the laboratory were recalculated and compared with the recommended needs. Based on the work, it can be said that horses receive nitrogenous substances above the recommended values.
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