National Repository of Grey Literature 35 records found  beginprevious16 - 25next  jump to record: Search took 0.00 seconds. 
Origins of vertebrate hematiopoiesis
Svoboda, Ondřej ; Bartůněk, Petr (advisor) ; Divoký, Vladimír (referee) ; Živný, Jan (referee)
(ENGLISH) Hematopoiesis is dependent on the actions of hematopoietic stem cells (HSCs). This process is tightly controlled through a complex array of extrinsic and intrinsic factors. Even though the hematopoiesis seems to be well conserved across the disparate vertebrate animals, erythroid and thrombocytic differentiation have changed during the evolution of mammals. Specifically, adult mammalian red blood cells have the unique feature of being enucleated, and mammalian thrombocytes are not individual cells, but fragments of megakaryocytes, instead. It is likely that these enhancements provided a survival advantage to early mammalian species; however, they also bring up the question of evolutionary origin of these cells that studied using zebrafish (Danio rerio) model. First, it was necessary to generate a toolbox of a recombinant cytokines and optimized culture media that allowed us to manipulate zebrafish hematopoietic cells ex vivo in liquid and clonal cultures. Interestingly, teleost species underwent an extra duplication event during their evolution and as a result, two copies (paralogs) of some of the genes are present in zebrafish. This was also the case for majority of the cytokines from our toolbox and here, we provide functional characterization of these paralogs. Strikingly, our results...
Variabilityin egg shell pigmentation of great tit clutches
Kratochvílová, Anna ; Svobodová, Jana (advisor) ; Veronika, Veronika (referee)
Eggshell coloration in bird clutches shows a striking variability within species which has not yet been fully explained. Its character is determined by the deposition of two main pigments: blue-green biliverdin is responsible for the background colour while brown-red protoporphyrin is associated with the dark spot pattern. Considering the role and matabolism of these two pigments in the avian organism it was suggested that they might have an important impact on the oxidative stress levels and their deposition into the eggshell is therefore suggested to possibly reflect the body condition of laying females during the laying periods. This is also the basic assumption for the signalling hypothesis of eggshell coloration which predicts the eggshell appearance to reflect the female body condition and individual health status or directly indicate aenemia in birds (aenemic hypothesis). Here it was tested whether there is a relationship between parameters representing the body condition of female great tits (Parus major) and the characteristics of protoporphyrin maculation of their eggs. Female body condition was expressed by standardized body weight and the selected haematological parameters (heterophil to lymphocyte ratio and relative immature erythrocyte counts). Eggshell coloration was characterized by spot colour (hue, saturation and brightness), spot counts and the reflectance of the background colour. It was found that females with higher heterophil to lymphocyte ratio laid eggs with more spots and higher reflectance of the background colour in some nesting seasons. Eggs with more spots on its surface were also laid by females with higher immature erythrocyte counts. These results suggest that more intensive deposition of protoporfyring into the eggsell can indicate worse body condition of the laying females. On the other hand, it was also found that heavier females laid eggs with lower reflectance of the background colour. Despite this discrepancy, these results are not inconsistent with the pressumptions of the signalling hypothesis and they partially support the aenemia hypothesis. However, the above mentioned dependencies were inconsistent among the nesting seasons, indicating that further important determinants must be considered in the avian eggshell coloration.
Detection of blood elements
Kadlček, Václav ; Kolář, Radim (referee) ; Lamoš, Martin (advisor)
Thesis deals with the detection and subsequent blood elements classification. Blood elements are described mainly in terms of optical features, that is used for digital image processing. Furthermore, available pre-processing theory, image analysis and methods of classifikation are discussed. Acquired knowledges are applied in MATLAB. Image Processing Toolbox is a pillar for that work within this programming environment. The program includes user interface, thus facilitating communication with the program. The program was tested on blood smear images and the results were evaluated.
Fish excretion of ammonia under different oxygen environmental conditions
MÜLLEROVÁ, Lucie
The aim of this work was to find out and compare amount of ammonia nitrogen excreted by fish in different oxygen saturation of water. Experiments (preliminary, main and additional) were made with ornamental form of common carp (Cyprinus carpio f. Koi) at Laboratory of Aquatic Toxicology and Ichtyopathology RIFCH in Vodňany. The preliminary (orientation) experiment was made in three different dissolved oxygen concentrations (I. 0,65 - 2,66; II. 2,43 - 5,70; III. 6,40 - 6,50 mg.l-1 O2) and fish production of ammonia nitrogen after 2 hours was I. 24,61; II. 85,29; III. 70,19 mg N-NH4+ per 1 kg of fish weight. The fish were also exposed to different oxygen conditions (hypoxia0,76 - 1,46; normoxia 9,8 - 9,46 mg.l-1 O2) in the main experiment which was repeated six times. Detected production of ammonia nitrogen in recalculated to 1 kg fish weight was 25,01 +- 3,14 mg N-NH4+ by the fish in hypoxia and 32,56 +- 4,08 mg N-NH4+ by the fish in normoxia after two hours of experiment duration. Detected difference was statistically significant (P < 0,05). Haematology and biochemical blood examination of fish which were exposed to hypoxia proved statistically significant increasing number of leukocytes, value of haematocrit, concentration of ammonia and glucose was made in the end of experiment. The additional experiment was repeated five times, the fish were exposed to hypoxia there (0,99 - 1,21 mg.l-1 O2) and the control fish were kept in water with concentration of dissolved oxygen between 7,67 - 9,11 mg.l-1. Statistically significant differences in ammonia nitrogen production were already found out in these groups of fish after two hours of experiment duration and difference increased markedly after 4,5 hours (fish production of ammonia exposed to hypoxia 47,92 +- 4,91 mg.kg-1 and in the control fish 101,53 +- 8,31 mg.kg-1). Production of ammonia by the fish originally exposed to hypoxia almost aligned to production of control fish during 2,5 hours after an aeration had been added to the fish in hypoxia. Production of ammonia nitrogen was 93,38 +- 17,82 mg.kg-1 by the fish originally exposed to hypoxia and 110,13 +- 18,21 mg.kg-1 by the control fish. This difference was not statistically significant yet. The results of experiment proved that fish ability to excrete ammonia from body is closely connected with oxygen conditions in water environment.
Qualitative parameters of erythrocytes in selected animal species
BÖHMOVÁ, Václava
The goal of the thesis is to evaluate the haematologic indicators of red blood cells depending to the physiological condition and yield of cattle, sheep and dogs. The evaluation of qualitative parameters of red blood cells included 59 dairy cows, 57 meat cows, 62 sheep and 73 dogs. The evaluation of the haematologic parameters of cattle was performed based on the production (yield) type and by season; that of sheep, by season, age and sex of lambs; and that of dogs, by sex, age and size - weight. The yield types showed statistically significant difference between the number or erythrocytes, haematocrit, haemoglobin, MCV and MCH concentration. The dairy cows showed seasonal fluctuations of the number of erythrocytes, haematocrit and haemoglobin; the meat cows showed fluctuations of the haemoglobin, MCH and MCHC values. The age influenced higher values of erythrocytes in sheep and lower values of MCV and MCH in lambs. The sex of lambs did not lead to significant differences. The evaluation of dogs by age showed differences of haematocrit and haemoglobin values. The dog size (weight) and the sex did not have demonstrable influence on haematologic values. Anaemia was found in 36 % dairy cows (it did not occur in meat cattle) and in 2 sheep (3 %). By most authors, anaemia was not found in dogs.
Hematological changes in fish exposed to nitrites
FRANĚK, Roman
The aim of the thesis was to determine the effect of nitrite on hematological indices of rainbow trout (Oncorhynchus mykiss) and Nile tilapia (Oreochromis niloticus). After the fish were exposed to various concentrations of nitrites were determined 48hLC50. For the main test only fractional concentrations of these values were used. For rainbow trout it was 8 mg.l-1 NO2?, for Nile tilapia 11 mg.l-1 NO2?. The exposure of both species lasted for 48 hours. From fish blood were made blood smears to determine the influence of nitrite on size changes of erythrocytes and hematological parameters were set also. The effect of nitrite on changes in the ultrastructure of erythrocytes was determined by the electron microscopy. The erythrocyte nuclei of rainbow trout showed significant (p <0.05) shrinkage. The images of the electron microscope showed an increased amount of changes, especially in the form of various units within the cytoplasm of erythrocytes, was also visible nuclei shrinkage. There was significant (p < 0.01) reduction in the amount of hemoglobin and significant (p < 0.01) increase in the concentration of methemoglobin levels of the exposed groups. In the number of erythrocytes and hematocrit were not detected any changes. Hematological parameters of Nile tilapia did not show any size changes in the measured parameters, no changes were detected in the count of erythrocytes, hemoglobin and hematocrit values.
The genome size determination in sturgeons using 2-D a 3-D image cytometry.
SRP, Jiří
The genome size of evolutionary polyploid, neopolyploid and hybrid sturgeons is well known for its high variability. Aim of this study was 1) to specify the genome size of polyploid and neopolyploid sturgeons using an analysis of 2-D and 3-D images of specifically stained cells nuclei, 2) to evaluate the samples of populations for cytogenetic analysis needs and thereafter, 3) to compare both methods and record the data either for next research or for negative selection from the broodstock. This test has been done at the laboratory of molecular, cellular and quantitative genetics, Faculty of Fisheries and Protection of Waters USB in Vodňany using all sturgeons spawners and using samples obtained from some foreign fish farms which cooperated with the faculty. The samples included A. ruthenus, A. baerii, A. stellatus, A. gueldenstaedtii and Huso huso, intentionally bred hybrids of A. gueldenstaedtii (8n) x A. baerii (12n), A. baerii (8n) x A. ruthenus (4n), A. gueldenstaedtii (8n) x A. baerii (10n) a A. gueldenstaedtii (8n) x A. ruthenus (4n). As methods have been chosen image cytometry and confocal microscopy which use image digitalization and subsequently its computer analysis. The genome size was measured from the size of specifically stained nuclei of erythrocytes in specimens sampled. Result of this study was measuring the genome size in sturgeons under study using different methods, recording the obtained data, description of spatial conformation changes of cell nucleus with increasing ploidy level and deduction of impact to their physiology and comparing the methods between each other. The conclusion is necessity of another sturgeons genome size determination , choice of the best methods for more effective search and research of non-standard individuals and subsequently an examination of their physiological differences.

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