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Farmaka ve vodním prostředí a jejich vliv na ryby
BURKINA, Viktoriia
In this thesis, the impact of atenolol, verapamil, dexamethasone, clotrimazole, and PBSA on the physiological condition and health of rainbow trout (Oncorhynchus mykiss) were studied in vivo and in vitro. The sub-chronic test of atenolol, including at the environmentally relevant concentration, demonstrated that only the fish exposed to atenolol at a concentration of 1000 ?g?L-1 may be at a higher risk of oxidative stress. The second pharmaceutical compound studied was an L-type calcium channel blocker, verapamil. Despite the relatively high concentration of verapamil included in the experiments, the rates of seven hepatic CYP450-mediated reactions (EROD, MROD, PROD, BFCOD, COH, and PNPH) were unchanged in the exposed rainbow trout. This indicates that the activities of the selected CYP450 enzymes were not affected. Exposure to the highest concentration of PBSA (1000 ?g?L-1) led to significantly inhibited glutathione reductase activity. The activities of the EROD, MROD, and PROD enzymes gradually increased, beginning at the environmentally relevant concentrations. We suggest that long-term exposure to PBSA could cause oxidative stress in fish, as indicated by the decreased activity of GR. Moreover, PBSA could interact with intracellular receptors due to the elevated activities of CYP1A (EROD and MROD) and CYP2B (PROD). Rainbow trout showed multiple responses after exposure to clotrimazole. Changes in the haematological parameters in the exposed rainbow trout suggested that the immune system and haemoglobin synthesis were affected. The antioxidant defence enzymes that responded to the clotrimazole exposure influenced the oxidative stress status of the fish. Sub-chronic exposure to clotrimazole did not lead to oxidative stress in any of the fish tissues studied, as indicated by the unchanged TBARS levels. Hepatic energetic pathways were activated in the tested groups after 42 days of exposure to clotrimazole. High levels of glutathione S-transferase were seen in the liver and gill tissues, possibly associated with the detoxification of clotrimazole. The interaction of clotrimazole with intracellular receptors can be expected due to the changes in the catalytic activities of CYP1A1 and CYP3A. The BCF levels in the muscle tissue suggest a moderate bioaccumulation of CLO. The relatively long elimination period for CLO in the fish kidney (half-life = 29 days) may imply a greater potential for adverse effects in this organ. This finding is significant in view of the structural disturbances that appeared in the kidney and testis. The changes observed in the kidney were most prominent in the tubular epithelial cells. Changes in the gonads were only visible in the male specimens, and the pathological changes in the testis may indicate a disruption of steroidogenesis. The potential of clotrimazole and dexamethasone to inhibit CYP450 enzyme activity in rainbow trout hepatic microsomes was investigated in vitro. Clotrimazole non-competitively inhibited EROD activity in the hepatic microsomes, while BFCOD activity was competitively inhibited. PNPH activity was only slightly reduced in the presence of clotrimazole, indicating that it does not significantly interact with CYP2E1. The presence of dexamethasone in the incubations did not affect any of the CYP450 enzymes investigated. Everything considered, the results of the study confirmed that the presence of clotrimazole in the environment is of concern with respect to its impact on the health status of fish. In this thesis, the data of the actual effects of several PPCPs on fish were discussed. Based on the response of selected molecular endpoints, the cardiovascular and anti-inflammatory drugs studied do not present a significant risk for fish, while the antifungal drug and UV-screening agent that were tested may disrupt several physiological processes in fish.
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Seasonal changes in the metabolic profile of dairy cows
KADLECOVÁ, Lenka
V teoretické části mé diplomové práce bylo cílem zpracovat přehled literatury, která se zabývá chovem, výživou a zdravotními problémy dojených plemen skotu v České republice a významem preventivních metabolických vyšetření. Dále pak popsat postup provádění a hodnocení metabolických profilových testů u dojnic. Praktická část byla zaměřena na zhodnocení vybraných ukazatelů metabolického profilu u dojnic plemene holštýn a český strakatý skot na rodinné farmě Velký Bor, kdy dojnice plemene holštýn dosahovaly užitkovosti 7450 litrů mléka za laktaci a dojnice český strakatý skot 6725 litrů mléka za laktaci. Vyhodnocování probíhalo v metabolicky nejnáročnější fázi laktace, tedy v období po porodu a ve vzestupné fázi laktace. Výsledky ukazují, že při uvedené užitkovosti dojnic plemene holštýn, která byla o 725 litrů vyšší než u dojnic plemene český strakatý skot, mezi metabolická rizika patří nedostatek Ca, Na a energetický deficit. To může vést k vyšší pravděpodobnosti vzniku metabolických onemocnění, především v období po porodu, oproti dojnicím český strakatý skot, které byly z hlediska užitkovosti méně zatíženy. Z hlediska ročního období a rozdílné krmné dávky v zimním a letním období dojnic nebyly výrazné rozdíly v hlavních sledovaných parametrech v krevním séru a moči, které by poukazovaly na vyšší riziko vzniku metabolických onemocnění. Avšak hodnoty bližší zvoleným normám vykazovaly profily v zimním období.
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Children with Phenylketonuria in kindergarten
BLAHOVCOVÁ, Veronika
This bachelor thesis is focussed on the problematic approach towards children with metabolic disorder ? phenylketonuria in a family and an environment of kindergarten. Congenital metabolic disorders lead to lack of certain substances in organism, or, on contrary, accumulation of them. Such disorders have various clinical displays, from harmless ones (often without symptoms) thru severe handicaps of physical and mental development to life-threatening states. The thesis is focussed on approach of parent as well as kindergartener towards child and it adverts to necessary adherence to diet restrictions.
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Effect of temperature, fish size and feeding on oxygen consumption and ammonia excretion in the Nile tilapia (Oreochromis niloticus)
DENKOVÁ, Adéla
Aim of this work were to assessed the impact of feeding, temperature, stocking density, fish size and water temperature on ammonia excretion and oxygen consumption of Nile tilapia (Oreochromis niloticus) in recirculating system. Concentration (saturation) of oxygen, water temperature and pH were measured using multimeter and concentration of ammonia was assessed by direct Nessler method. For assessing of effect of fish size, three groups of tilapias weighed 25, 65 and 140 g were established, each group in four replicates. For assessing of effect of feeding was tilapias (body weight 65g) divided into groups fed continuously, two meals per day and four meals per day, each group in four replicates. For assessing of effect of stocking density was tilapias (body weight 65g) divided into groups of 20, 50 and 80 kg.m-3, each group in four replicates. All experiments were performed for water temperature of 23, 27 and 31 °C and for fed and starved fish. Mean daily oxygen consumption was higher for smaller fish categories than for bigger ones and grow rapidly after feeding. The kind of feeding had impact on diurnal fluctuation of oxygen consumption. It was also confirmed that tilapia can survive low level of oxygen concentration for a quite long period.
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The metabolism of selected species of predatory aquatic insects
KLEINOVÁ, Miroslava
Title: Metabolism of selected species of predatory aquatic insects. Target: The main objective of this study was to analyze metabolic rates of predatory aquatic insects, in my case dragonflies (order Odonata, suborder Anisoptera). Different instars of several species of dragonflies were observed. Another objective was to determine the dependence of the metabolic demands on the species and size of the individual, create tables and graphs summarizing the most important results and perform a basic statistical analysis. Methods: In my work I used the method of measuring the consumption of dissolved oxygen, using a polarographic determination of oxygen concentration with a membrane-covered oxygen sensor. Results: The rate of metabolism on the unit weight decreased with increasing weight and size, which corresponds to the assumptions of metabolic theory of ecology.
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