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Effects of alpha-zearalenol on hyperactivation and acrosomal reaction of the boar sperms
Doleželová, Kateřina ; Rajmon, Radko (advisor) ; Marie, Marie (referee)
Alpha zearalenol is a derivative of the mycotoxin zearalenone, which is commonly found in agricultural crops and commercial feed. It is a secondary metabolite of filamentous fungi of the genus Fusarium. The alpha zearalenol is the result of a biotransformation of zearalenone in the liver and intestinal tissue. When the zearalenone is metobolised this way, it is able to compete for the binding sites of estrogen receptors because the structure is very similar to 17 beta estradiol.
Toxicity of alpha zearalenol therefore lies in an estrogenic stimulation, which induces morphological and functional changes in the reproductive organs and gametes. Toxicity is manifested on the male gamete by reducing viability, motility and the portion of sperms capable of undergoing acrosome reaction.
The aim of this study was to evaluate the effect of alpha zearalenol on the hyperactivation and acrosome reaction of boar sperm depending on the concentration and duration of exposure to mycotoxins.
For the purposes of this study we used two methodologies and the short term chilled commercial insemination doses which were kept in a box with the temperature of 17 degrees of Celsius. The two methodologies had a different count of used concentrations of alpha zearalenol and exposure time. Acrosome reaction of sperms was assessed in both methodologies, while the share of hyperactive sperm was assessed only in the second methodology.
The first methodology did not prove any effect of alpha zearalenol on acrosome reaction, but the second methodology has proven a positive effect of concentrations 5, 10 and 20 uM alpha zearalenol on acrosome reaction of boar sperm. Individual values of parameters from CASA analysis (VCL, ALH, LIN and WOB), which were used for evaluation of hyperactivation of boar sperm, were not affected by any used concentrations of alpha zearalenol.
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Vliv podmínek skladování na mikrobiologickou jakost zvěřiny
Macháčová, Lucie
The theoretical part of my thesis focuses on venison, its composition and microorganisms that devalue its shelf life. The purpose of practical part of my thesis was to monitor changes in the number of selected microorganisms in samples of vacuum-packed meat of deer, roe deer and wild boar after seven days of storage in a refrigerator at 4 ° C. The study included a total of six series of samples meat of red deer, roe deer and wild boar. The monitored microbiological criteria were Escherichia coli, coliform microorganisms, psychrotrophic microorganisms, lactic acid bacteria and the total number of microorganisms. The total number of microorganisms presents in deer meat samples increased by 1.62 log CFU.g-1 to 7.55 log CFU.g-1, in roe deer meat samples by 1.73 log CFU.g-1 to 7.65 log CFU. g-1 and in wild boar meat samples by 1.4 log CFU.g-1 to 7.61 log CFU.g-1. The highest increase of microorganisms, in most of determination, was in samples of roe deer, the smallest in samples of red deer. Wild boar indicates the biggest microbial contamination on the first day of storage. Microbiological determination of individual counts was performed in the laboratory of the Institute of Food Technology by using cultivation methods on plates. None of the observed samples of red deer, roe deer or wild boar exceed the limit of destruction (108 CFU.g-1) after one week.
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Vliv antioxidantů (selen, vitamin C a E) na spermatogenezi kanců
Svačinová, Lucie
The purpose of this dissertation is the verification of antioxidants, the vitamin C, the vitamin E and selen influence on the spermgenesis of breeding boars. The ejaculate quality was evaluated with the use of qualitative and quantitative figures (the ejaculate volume, the motility, the sperm concentration and the number of abnormal sperms). The experiment was done at the boars' insemination station (ISK) in Velké Meziříčí. In the experimet, there were 12 boars of DUROC race involved. The boars were split into two groups. By the first boars experimental group (n=6) there were added into the feeding batch 350 mg of the vitamín C (ascorbe acid); 70 mg of the vitamín E (alfatocoferol) and 0,5 mg of selen (selenomethionin) per one kilogram of this special diet. The second group of boars was used as the checking group and the volume of the vitamin C, the vitamin E and the selen was not increased in their diet. The experiment was running for 90 days (June -- August). At the checking group the volume of their ejaculate was increasing untill the 60th day of the experiment, in the final stage it has significantly dropped, totally by -19%. By the experimental group, the volume of the ejaculate was constantly increasing trend and the total volume increase during the experiment duration was +32%. The sperm motility at the checking group has decreased from the original 69% down to 54%, while at the experimental group it has increased by approximatelly 1%. The sperm concentration check -- by the checking group it has increased by +6% and by the experimental group the sperm concentration has decreased by -24%. The number of abnormal sperms at the checking group has increased by +1% and by the experimental group the number of pathologic sperms has increased by +30%. Based on our results it is possible to say, that selen, the vitamin C and vitamin E do not have a provable effect on the boars ejaculate quality. But we must také into the consideration also the summer season, during which the experiment was provided. There were higher temperatures affecting the animals, which could have negative influence on the results.
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Hodnocení parametrů osvětlení na inseminační stanici kanců
Pecinová, Hana
The thesis aims to evaluate hygienic standard of boars breeding which is the base for good reproductive skills achievement. In relation to the quality of the semen, the lighting parameters play significant role among the microclimate conditions. In this experiment the light intensity was evaluated at weekly intervals from March 2012 to March 2013, in ISK Velké Meziříčí. 88 boar breeds were put into the experiment -- duroc, danish duroc and landrace. Light intensity was evaluated in relation to the parameters of sperm quality, which are: motility (%), semen volume (ml), sperm concentration (thousand.ml-1) and the proportion of sperm with pathological changes (%). The analysis of collected data showed statistically significant light effect on the ejaculate quality (P=0,001). When the light intensity have been growing (65,7 lx), the capacity and portion of pathological changes decreased (to 231,3 ml from 279,7 ml and 8,7 % from 9,6 %), while the concentration increased (426,8 thousand.ml-1 from 346,2 thousand.ml-1) in opposite to lower level of light intensity (52,3 lx). During summer the overall quality decreased, which can be caused by both, the intensity of light but also the thermal stress factor.
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