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Eliminace výskytu vajec s poškozenou skořápkou u nosných hybridů na konci snášky
Horník, Radek
The deterioration of eggshell quality depending on the age of the laying hens causes significant economic losses for table egg producers. The aim of the experiment was to determine whether feeding vitamin D3 in the form of 25-hydroxyvitamin D3 would improve eggshell quality after 46 weeks of flock age. Two houses with flocks of Lohmann Brown-Classic laying hens housed in enriched cage technology were included in the observation. Both houses were fed the same feed mixture from the same supplier. From 38 weeks of age onwards, eggs were collected at regular two-week intervals in a number of 60 eggs from each house for each observation. Egg weight and eggshell strength, weight and thickness were determined for these eggs. From the 46th week onwards, 25 hydroxyvitamin D3, its hydroxy analogue, was started in the feed mixture in addition to vitamin D3 at one house. Monitoring of the above parameters was continued until the 67th week of age. It was found that the eggs were lighter on the shed where 25 hydroxyvitamin D3 was fed (P < 0,001), which was due to the fact that the eggs were conclusively lighter on this shed before the experimental intervention (P < 0,05). The egg weight was closely related to the eggshell weight, which was also conclusively lower on the experimental shed (P < 0,05). There was no conclusive difference in eggshell strength and thickness between the sheds. Egg and eggshell weight and shell thickness were significantly influenced by flock age (P < 0,001). There was no positive effect of 25 hydroxyvitamin D3 on eggshell quality.
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Analýza obsahu významných nutrientů v tropickém ovoci a v jejich škůdcích
Remencová, Julie
The diploma thesis is focused on analysis of selected elements of tropical fruits and their pests. The aim of the thesis was to find a relationship between mineral content of tropical fruits and their pests and to clarify whether the found correlations can be used for targeted pest management. The mediterranean fruit fly (Ceratitis capitata) and peach fruit fly (Bactrocera zonata) are one of the most dangerous and economically important species of Tephritidae family causing significant economical looses estimated in hundreds of millions of dollars per year. The theoretical part focuses on general description, production and consumption, chemical content and importance of individual analysed tropical fruit species. Literature review deals with selected elements – calcium, magnesium, iron, zinc, manganese and copper from the point of view of importance in human nutrition. The practical part describes analyses of the above mentioned elements using flame absorption spectrometry in samples of mango (Mangifera indica), mandarin (Citrus unshiu), kaki (Diospyros kaki) and pomegranate (Punica granatum) and samples of two fruit fly species C. capitata and B. zonata. From the correlations of elements contents in tropical fruits and their pests follows that the determination of calcium can be used for identification of the origin of the pest because a significant correlation was found only between the content of calcium in mandarin and C. capitata fed on mandarin.
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Determination of selected elements in cereal flours and their gluten-free alternatives
Venclová, Veronika ; Hraníček, Jakub (advisor) ; Nováková, Eliška (referee)
This study deals with the determination of calcium, magnesium, phosphorus, potassium, sodium, iron, zinc, copper, manganese and molybdenum in cereal gluten flours and its gluten-free alternatives. The flour samples were digested using a microwave device and the elements in solution were subsequently determined using an inductively coupled plasma mass spectrometer. Optimization of the digestion of the selected flours was performer prior to the actual determination of the elements. The aim of the work was to determine the above listed elements in the flour samples and to establish a basic overview of the elemental composition of the different flours. This overview and comparison of the different flours is intended to help the people with celiac disease to choose gluten-free alternatives to wheat flour. Keywords Inductively coupled plasma mass spectrometry, microwave digestion, calcium, magnesium, phosphorus, potassium, sodium, iron, zinc, copper, manganese, molybdenum, wheat flour, gluten-free flours, celiac disease
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Aboveground litterfall fluxes of selected elements in central European temperate forest
Bašta, Jan ; Oulehle, Filip (advisor) ; Chuman, Tomáš (referee)
5 Abstract Aboveground litterfall is the most important intrasystem flow in the temperate forest ecosystem. It is also the largest input flux to the soil surface for most of the macronutrients (N, P, Ca, Mg, K). However, under Central European conditions, studies on the magnitude of this flux in relation to elemental stocks are lacking. GEOMON Small Forest Catchment Network is used to investigate long-term trends in nutrient cycles in temperate forests of Central Europe and the human influence on them. As part of this network aboveground litterfall collectors were placed in 14 catchments at a total of 19 sites at the end of 2019. Litterfall was then collected bimonthly, weighed and sorted into different fractions. These fractions were analyzed to determine the concentration of the elements of interest. From these values, the fluxes of the elements in the aboveground litterfall were calculated. The observed values were compared with the characteristics of the individual sites and the element budgets in the catchments. The monitored elements can be ranked according to the size of the flux of the element through the aboveground litterfall in relation to other inputs of that element to the soil as follows: C, P, N, Ca, Mg and K. The average amount of aboveground litterfall in the GEOMON network is 4.6...
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Determination of calcium, magnesium and phosphorus in selected types of animal bones
Škardová, Alice ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
This research focuses on the elemental analysis of selected elements (calcium, magnesium, and phosphorus) within the bones of various animal species, aiming to make comparative nutritional assessments. The obtained bone samples were subjected to mechanical grinding and then quantitatively weighed into collapsible cartridges. Using high-pressure microwave decomposition with the incorporation of nitric and hydrochloric acid, the samples were transformed into solution form, which was then appropriately diluted. The analysis of the liquid samples was carried out using a mass spectrometer with inductively coupled plasma. The observed composition for each sample was calculated using the calibration curve, accounting for both sample mass and dilution factors. All results obtained exceeded the detection limit for calcium 0.38 mg/l, magnesium 0.037 mg/l, and phosphorus 0.078 mg/l. The main finding of this research is the complete understanding of the elemental makeup present within the bones of distinct animal species.
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Specifics of plant mineral nutrition on serpentine soils
Škopová, Lucie ; Tylová, Edita (advisor) ; Lhotáková, Zuzana (referee)
Serpentine is a metamorphosed ultramafic rock on which a substrate with specific combinations of properties responsible for creating the typical inhospitable conditions for plant life is formed. The characteristic chemical composition of serpentine soils consists of a low ratio of Ca:Mg ions, low content of biogenic elements (P, K, N) and a high concentration of heavy metals (Co, Cr, Ni). Abiotic factors such as rocky surface, shallow soil and lack of water also hinder the life of local plant. The aim of this bachelor thesis was to summarize the complex of characteristic serpentine phenomenon that in many ways create stress conditions for plants growth. Thanks to this specificity, the serpentine areas are characterised by a specific flora and vegetation with a number of endemics. This work focuses on the specific mineral nutrition of plants and summarizes the knowledge on the mechanisms of adaptation of plants growing on serpentine substrates. I focused mainly on the typical low Ca:Mg ion ratio in serpentine soil and described the functions of these elements in plants and the stress effect of excess Mg. Throughout this work, I also address the mechanisms of uptake and transport of serpentine-relevant nutrients in the plants identified so far. In conclusion, I discuss ability of plants to survive in...
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Lactose intolerance and adding dairy products into the diet
KÁCHOVÁ, Nikola
The bachelor's thesis entitled "Lactose intolerance and the inclusion of dairy products in the diet" is divided into two parts. The theoretical part deals with the issue of lactose intolerance, calcium, discusses the importance of milk and dairy products in the diet and also deals with dietary solutions. The practical part is focused on the general awareness of people diagnosed with lactose intolerance, the inclusion of milk and dairy products in the diet and their evaluation. The aim is to map the inclusion of milk and dairy products in the diet of patients with lactose intolerance and to evaluate whether the diet of patients with lactose intolerance is adequate in terms of energy, macronutrient and calcium intake. The research is carried out using a quantitative method using a questionnaire. I obtained respondents, people diagnosed with lactose intolerance, with the help of doctors and nutrition therapists, but also with me personally during the internships. I also evaluated weekly menu entries using by Nutriservis Professional. From the obtained data, I found out that patients with lactose intolerance include milk and dairy products in the diet sporadically. Their lactose-free variants are included in the diet more often, but the survey found that they prefer plant alternatives to milk and dairy products. The recommended calcium intake was not achieved in selected respondents if they do not supplement calcium. Dietary calcium intake averages 394 mg/day. More than half of the respondents do not achieve the required intake of energy, macronutrients or calcium. This bachelor's thesis can serve as a source of information for patients with lactose intolerance, or for students interested in this issue, professionals and the general public. It points to deficiencies in the diets of patients with lactose intolerance.
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Determination of calcium in food supplements
Hubčuková, Karmelita ; Hraníček, Jakub (advisor) ; Sobotníková, Jana (referee)
Tato bakalářská práce byla zaměřena na stanovení vápníku ve vybraných potravinových doplňcích s využitím plamenové atomové absorpční spektrometrie. Nejdříve byla prováděna optimalizace podmínek s využitím plamene acetylen-vzduch a následně s využitím plamene acetylen-oxid dusný. Optimalizovanými parametry byla výška paprsku nad hranou hořáku, horizontální poloha hořáku, šířka absorpčního prostředí, průtoková rychlost acetylenu a oxidu dusného. Byla sestrojena kalibrační závislost stanovení vápenatých iontů a odpovídající meze detekce a stanovitelnosti. Následně byly vybrané vzorky potravinových doplňků několika způsoby převedeny do roztoku. Vyzkoušeno bylo rozpouštění v deionizované vodě, rozpouštění v koncentrované kyselině dusičné a rozklad pomocí mikrovlnného tlakového zařízení. Experimentálně bylo stanoveno množství vápníku v potravinových doplňcích, které bylo porovnáváno s údaji uvedenými od výrobce. Správnost měření byla ověřena analýzou referenčního materiálu.
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