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Toxicita selenových nanočástic v živočišném organismu
Hledíková, Jana
The aim of this study was to verify the toxicity of selenium nanoparticles in an animal organism. Wistar albino rats were divided into five groups. Four groups of rats were fed a monodiet with added SeNP at doses of 0,5; 1,5; 3,0 and 5,0 mg Se/kg per feed dose. The experiment lasted 28 days. During this, the weight of the animals was measured every 7 days (0, 7, 14, 21, 28). After putting to death the animals at the end of the experiment, some blood parameters and histopathology of selected tissues were determined. Total antioxidant capacity (TAC), glutathione peroxidase (GPx), superoxide dismutase (SOD), alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), glucose, total protein and albumin were diagnosed in the blood. Blood and liver selenium levels were analyzed and liver function tests were performed. Histopathological evaluation of liver and intestinal tissue was performed. The weight gain of the rats did not show differences between the tested groups. Compared to the control group, the selenium content in the blood and liver increased in the tested groups. However, selenium content in the liver did not increase in the test groups in a dose-dependend manner. No differences in TAC and ALP and AST aktivity were found. A significant reduction in ALT aktivity was observed in the test groups compared to the control group. SOD aktivity was reduced in the SeNP test group with 5 mg Se/kg compared to all other groups. GPx aktivity had a slightly increasing trend depending on the dose of SeNP, but without a significant (p <0,05) effect. Histopathological examination revealed damage to the hepatic parenchyma and intestinal epithelium that was dose-dependend on SeNP. From this study, it can be concluded that short-term supplementation of SeNP may be safe and beneficial, for example in selenium deficiency or for therapeutic purposes.
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Péče o mláďata hospodářských zvířat v ekologickém chovu
Hledíková, Jana
This bachelor thesis deals with breeding of the young farm animals in organic farming. At first, the legislation related to the ecological system of farming is mentioned. Furthermore, objectives and rules of organic production follow. The principles of organic animal husbandry are described in more detail. The next part is devoted to specific types of farm animals, namely cattle, sheep, goats and pigs. The important aspects of rearing of the youngs, specifically housing, nutrition of females and youngs and weaning, are described in these livestock. Afterwards the comparison of organic and conventional farming system is made.
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