National Repository of Grey Literature 18 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
Možnosti snížení obsahu dusíkatých látek v krmných směsích pro brojlerová kuřata
Rada, Vojtěch
The aim of the dissertation was to investigate the effect of exogenous protease (EP) in feed mixtures (FM) for broiler chickens with reduced crude protein (CP) content by 4 and 8 % on growth parameters, carcass quality, apparent ileal digestibility of amino acids and protease activity in the jejunum of broiler chickens. At the same time, the effect of EP on the given parameters was investigated at the increased level of rape seed meal (RSM) in FM. The addition of EP to KS with a 4% reduction in CP did not have a statistically significant (P> 0,05) effect on growth, conversion and feed intake, quality of carcass, nor on the apparent ileal digestibility of amino acids and protease activity in jejunum of the broiler chicken. Higher content of RSM in FM with a 4% CP reduction negatively (P <0.05) affected the protease activity in the jejunum. The addition of EP into FM with an 8% CP reduction statistically (P <0.05) increased the average live weight of broilers on the 17th and 24th day of the age. At a higher age, EP has not influenced on the live weight of broilers and the overall feed conversion. Females chickens consumed FM with 8% CP reduction had a significantly lower (P <0.05) weight of breast muscle and carcass value. Adding protease to FM with an 8% CP reduction statistically significantly (P <0.001) decreased the digestibility of Pro and Tyr (P <0.05). The EP had no significant (P> 0.05) effect on protease activity in the jejunum of broilers with FM intake with an 8% CP reduction. Higher content of RSM in FM with an 8% CP reduction significantly decreased (P <0.05) apparent ileal digestibility of Pro and significanlty (P <0.05) increased protease activity in broilers jejunum.
Deformation response of polydimethylsiloxane substrates subjected to uniaxial quasi-static loading
Vinařský, V. ; Martino, F. ; Forte, G. ; Šleichrt, Jan ; Rada, Václav ; Kytýř, Daniel
To investigate cellular response of cardiomyocytes to substrate mechanics, biocompatible material with stiffness in physiological range is needed. PDMS based material is used for construction of microfluidic organ on chip devices for cell culture due to ease of device preparation, bonding, and possibility of surface functionalization. However it has stiffness orders of magnitude out of physiological range. Therefore, we adapted recently available protocol aiming to prepare substrates which offer stiffness in physiological range 5−100 kPa using various mixtures of Sylgard. An in-house developer loading device with single micron position tracking accuracy and sub-micron position sensitivity was adapted for this experimental campaign. All batches of the samples were subjected to uniaxial loading. During quasi-static experiment the samples were compressed to minimally 40% deformation. The results are represented in the form of stress-strain curves calculated from the acquired force and displacement data and elastic moduli are estimated.
Multi-channel control system for in-situ laboratory loading devices
Rada, Václav ; Fíla, Tomáš ; Zlámal, Petr ; Kytýř, Daniel ; Koudelka_ml., P.
In recent years, open-source applications have replaced proprietary software in many fields. Especially open-source software tools based on Linux operating system have wide range of utilization. In terms of CNC solutions, an open-source system LinuxCNC can be used. However, the LinuxCNC control software and the graphical user interface (GUI) could be developed only on top of Hardware Abstraction Layer. Nevertheless, the LinuxCNC community provided Python Interface, which allows for controlling CNC machine using Python programming language, therefore whole control software can be developed in Python. The paper focuses on a development of a multi-process control software mainly for in-house developed loading devices operated at our institute. The software tool is based on the LinuxCNC Python Interface and Qt framework, which gives the software an ability to be modular and effectively adapted for various devices.
The effects of bacterial lysates on the gut barrier function and microbiota composition
Zákostelská, Zuzana ; Tlaskalová - Hogenová, Helena (advisor) ; Prokešová, Ludmila (referee) ; Rada, Vojtěch (referee)
Dynamic molecular interactions between the microbiota and the intestinal mucosa play an important role in the establishment and maintenance of mucosal homeostasis. Aberrant host- microbiota interaction could lead to many diseases such as inflammatory bowel disease. The aim of our study was to evaluate the commensal and probiotic bacteria activities and their ability to induce pathological or exert beneficial effects. The most important trigger for immune system development is an exposure to microbial components. Here, we show that there is a time window at about three weeks of age, which enables the artificial colonization of germ free mice by a single oral dose of cecal content. The delayed colonization by either inoculation or co-housing causes permanent changes in immune system reactivity, which may downgrade the results of experiments performed on first generation of colonized animals. In this thesis we report that even non-living commensal bacteria such as Parabacteroides distasonis (mPd) or well known probiotics such as L. casei DN-114 001 (Lc) possess anti-inflammatory effects in experimental model of colitis. The mechanisms that this effect is achieved by the lysate of L. casei DN-114 001 comprise: a) improvement in the gut barrier function, b) correction of the dysbiosis, and c) modulation of the...
Impact of pesticides on the gut microbiota of animals
Stehlík, Michal ; Rada, Vojtěch (advisor) ; Salmonová, Hana (referee)
Pesticides are substances used to control plant and animal pest in agriculture. They are very significant and important factor in both production and revenues. Nowadays it is almost impossible for farmers to dispense without these substances but their presence in the soil does not bring only benefits. About pesticides it is generally known that they may adversely affect either on the ecosystem or the human or animal body. As the result many substances had been banned from market. Pesticides and their residues are subject to many controls and laboratory analysis in order to prevent their negative effects. The aim of the thesis was to test the effect of pesticide (Roundup) on gut microorganisms. For the experiments we used bovine fecal samples and pure bacterial cultures isolated from various domestic animals for the testing of susceptibility to Roundup. We have determined specific growth rates of pure cultures cultivated on three different concentrations of Roundup and total counts lactobacilli, enterococci, E. coli and coliform bacteria of bovine feces cultivated on six different concentrations of Roundup In the first experiment, no correlation has been found between the concentration of glyphosate (active substance of Roundup) and counts of bovine intestinal bacteria. The effect of glyphosate on the growth of intestinal bacteria was visible at the second attempt. At the highest concentration of glyphosate 17 g/L. Growth curves reached considerably lower levels here than at lower concentrations of glyphosate. Control samples and the samples on the concentration of glyphosate 1.7 mg/L and 0, 17mg/L increased similarly in most cases. This implies that in these concentrations there was no inhibition of bacteria whatsoever. The least susceptible genera to glyphosate were lactobacilli. The highest susceptibility to glyphosate was detected in bovine bacteria and the lowest in chicken bacteria.
Characterization of bifidobacteria and lactobacilli isolated from intestinal tract of wild pigs
Šimurka, Julius ; Rada, Vojtěch (advisor) ; Švejstil, Roman (referee)
The microbiota of the gastrointestinal tract is considered as "acuqrated organ" located in a host organism. There are many performs of specific functions. The microbiota composition changes during the life of the individual, depending on his environment and nutrition. The process of identification and characterization of the bacteria from the intestinal microbiota is an important prerequisite for understanding the function of this "acuqrated organ". This work deals with the anatomy and physiology of the digestive tract (DT) of pigs and evolutionary and eating differences of wild and domesticated pig, for understanding the natural environment of bacteria from DT, which in turn affects the bacterial diversity of the intestinal microbiota. Also mentioned is the process of domestication, which influenced the present form of domestic pig. The work includes the characteristics of lactobacilli and bifidobacteria, which contains the descriptions, taxonomy, metabolism and habitats. The work also shows the insulating media used in practice for the isolation of bifidobacteria and lactobacilli from DT of pigs and methods of their identification and related methods of characterization. The available literature confirms the differences in the composition of microbiota DT between wild and domesticated pig, that correlate with other studies which study microbiota diversity of other domesticated and wild animals. The diversity studies of humans microbiota, also confirms the broad spectrum of bacterial species in primitive tribes of humans compared with urbanized man.
Microbiology of unfiltered beers from craft breweries and the possibility of shelf life extending
Janíková, Jolana ; Rada, Vojtěch (advisor) ; Chládek, Ladislav (referee)
In the last ten years can be recorded a multiple number of minibreweries, called sometimes craft breweries I tis not caused only by demand of kinds of beer characterised by special types of beer styles, but as well by the fact, that they are not anyway regulated and keep their natural taste and smell. The problém of unregulated (unfiltered and unpasteurized) beers starts by the contamination during their production and it may cause their relatively fast spoiling. Shelf life of these beers is e few weeks only. The time of their minimal shelf life is influenced by a lot of factors content of alcohol, rest extract and mentioned extent of contamination. The breweries called as industrial or commercional treat their beers by pasteurization or filtration which cause inactivation or killing of the microorganisms or their elimination. These beers are microbiologically stabile, they are not liable to quick spiling and i tis possible to insure their longer shelf life. Pasteurized a filterd beers show changes in their sensorial character. The aim of this diploma thesis was to determinate the condition of flash pasteurization of unfiltered beers with the aim of microbiological stability and simultaneously no changes of their sensorial quality. The experiment is finally in treatment unfiltered beer by differnt dosing of pasteurization units and following microbiological analysis, able to demonstrate the stability effect. The analysis were used with unfiltered and unpasteurized beers and with unfiltered beers where the pasteurization doses 20 PU, 30 PU, 40 PU, 60 PU, 80 PU and 100 PU were used. The idividual parameters were watched within the horizont of 4 months. The part of these tests was even microbiological analysis of the rinse water. Another task was to find out the dates from the microbiological controls of beer in selected small breweries, which use in order to heighten of microbiological stability, different kinds of filtration, to verify their effectivity and to appreciate their acceptability for minibreweries. The test showed the effectiveness of pasteurization of unfiltered beer with the rations 40 PU minimally. Where higher ratins were used could be seen apparent sensorial changes. The pasteurization of unfiltered beers are for craft breweries useful only in case of higher production of bottled beer or beer for export, because the financial expenses bound with provision flash pasteurizer are to big and for minibreweries mostly limiting. The kieselguhr filtration as well the ultrafiltration are for minibreweries unusefull, as they could not be able to insure such conditions that provide their proper affectiveness.
Molecular genetic characterization of vancomycin-resistant enterococci
Bubeníček, Karel ; Rada, Vojtěch (advisor) ; Igor, Igor (referee)
Summary Objectives and hypothesis: This thesis concerns the study of plasmids of vancomycin- resistant enterococci isolated from feces of American crows in the years 2012 - 2013 period. The hypothesis is that, in various environments, there is one or more types of epidemiologically significant vanA gene-carrying plasmids that are capable of horizontally spread. Methods: Based on PFGE method the number and size of plasmids were detected in selected isolates of vancomycin-resistant E. faecium. Using PCR method the isolates were subjected to detection of genes of replicases, relaxases and toxin-antitoxin system of plasmid-bound resistance genes. Using 19 primers were characterized types of Tn1546. Results: Of the 12 tested vancomycin-resistant isolates of E. faecium the following number and size of plasmids was proven using PFGE method: 2 isolates contained two plasmids (17%), 3 isolates contained three plasmids (25 %), 5 isolates contained four plasmids (42 %) and 2 isolates contained five plasmids (17 %). All isolates (n = 12) were then subjected to the detection of genes of replicases, relaxases and toxin-antitoxin system for typing of plasmids from each plasmid families. RepA_N family of plasmids: genes characterizing plasmids related to pRUM: rep17 in 11 isolates (92 %), gene Axe-Txe was detected in 5 isolates (42 %) genes characterizing plasmids related to pLG1: rep20 in 7 isolates (58 %) genes characterizing plasmids related to pAD1: relpAD1 gene was detected in one isolate (8 %) Inc18 family of plasmids: genes characterizing plasmids related to pIL501: rep1 gene detected in one case (8 %) genes characterizing plasmids related to pRES25: rep2 gene in 2 isolates (17 %) genes characterizing plasmids related to pEF1: relpEF1 detected in 11 isolates (92 %) pHTB family of plasmids: genes characterizing plasmids related to pHTB: rep22 gene was detected in 4 isolates (33%) and in 2 isolates gene relpHTB was detected (17%) RCR family of plasmids: genes characterizing plasmids related to pRI: positive detection of Rep14 gene in 8 isolates (67%) and in 4 isolates relpRI gene was detected Small theta-replicating plasmids: genes characterizing plasmids related to pEF418 plasmids: rep18a gene in 2 isolates (17%) genes characterizing plasmids related to pB82: rep18b gene was detected in one isolate (8%) genes characterizing plasmids related to pCIZ2: relpCIZ2 gene was detected in 9 isolates tested (75%) Types of transposon Tn1546 Using the PCR method types of Tn1546 were characterized. In 4 isolates (n = 12; 33 %) Tn1546 was characterized as a F3 type. In one isolate (8 %) Tn1546 was characterized as a type F5, in one isolate (8 %) as a type PP-16. In 6 isolates Tn1546 was untypeable. Most likely these are new, yet unknown types. Conclusion: This is the first study of plasmids of vancomycin-resistant isolates E. faecium isolated from feces of American crows. These results emphasize not only a high proportion of plasmids in individual isolates, but also a high proportion of genes with horizontal transfer.
Impact of pesticides on the gut microbiota of human
Kočová, Kateřina ; Rada, Vojtěch (advisor) ; Jakub, Jakub (referee)
Pesticides are substances or mixtures of substances used in agriculture against pests (animals, plants and parasitic fungi), who damage the crops, stocks of agricultural products, food and reduce livestock utility or threaten human health. The thesis consists of two parts. The first (theoretical) part describes composition and function of gut microbiota; pesticides and their classification, environmental transport and effects of these substances on human health, and glyphosate as the active substance of herbicide Roundup, its mechanism of action, environmental fate and proven effects of glyphosate on human. The aim of second (practical) part of this thesis was to test impact of pesticide Roundup on the gut microorganisms of human. The impact of pesticide was tested in in vitro pure cultures. Roundup was added in concentrations of glyphosate 17 g/L, 1,7 g/L and 0,17 g/L to the complex media and after cultivation the growth of microorganisms was evaluated. The next samples of stool were collected from human volunteers; these were cultivated similarly in the complex media with different concentrations of glyphosate. The total numbers of microorganisms, bifidobacteria, lactobacilli, enterococci and coliformn bacteria were defined after cultivation. When the pesticide was tested in pure cultures, concentration of 17 g/L glyphosate significantly inhibited total bacterial growth (P < 0.05), at lower concentrations no difference was observed. The cultivated microorganisms from samples of stool demonstrated only that bifidobacteria are sensitive to glyphosate at the highest used concentration of this pesticide compared with the control sample.

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4 RADA, Václav
6 Rada, Vojtěch
4 Rada, Václav
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