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Strategie oplozování u ryb s vnějším oplozením
SIDDIQUE, Mohammad Abdul Momin
Morphological properties, species specific differences, development, and function of egg envelopes are of importance for a better understanding of fertilization strategies as well as for captive reproduction. We reviewed morphology and the developmental stages of egg envelopes, mechanism of polyspermy block, and also the role of micropyle and cortical granules in polyspermy block for acipenserid eggs. The structure of the egg envelope is similar among the acipenserids, comprising an external envelope (thecal cells, basal lamina, and follicular epithelium), a five-layered oocyte envelope (adhesive layer, alveolar layer, epilayer, and zona radiata externa and interna) and a layer of oocyte matrix and cortical granules. The development of acipenserid egg envelope within the ovary comprises five stages, with further changes following fertilization. Moreover, we standardized the terminology used to describe the egg membranes which can minimize the confusions and be helpful for future work on acipenserids eggs as well as for other fish species. The sperm to egg ratio (required to fertilize eggs) and effects of pre-incubation of eggs in freshwater before fertilization were studied to standardized fertilization protocols for sterlet Acipenser ruthenus. Pre-incubation time had no effect on fertilization success at 430,000:1 and 43,000:1 sperm to egg ratios, while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5 min pre-incubation increased the fertilization rate than 10 min. Transmission electron microscopy showed that pre-incubation of eggs in water for <10 min did not trigger a cortical reaction, suggesting that a low sperm to egg ratio 0.5 to 1 min pre-incubation of eggs in freshwater prior to fertilization can enhance fertilization rate of sterlet (minimally do not change fertilization). The effects of pre-incubation in seawater and the duration of egg receptivity were determined for fresh and over-ripe sea bass eggs. Our results revealed a significant effect of pre-incubation time for both the fresh (P < 0.01) and over-ripe eggs (P < 0.01). The fresh eggs had a higher fertilization success than over-ripe eggs. Fertilization success of eggs significantly declined for both of these treatments after 3 min of pre-incubation clearly indicated that sea bass eggs are able to be fertilized by sperm for up to 3 min after release into seawater. Effects of pre-incubation of eggs and activation medium on the percentage of eyed embryos for Ide Leuciscus idus were examined. At the eyed-egg stage, pre-incubation time was significant for the freshwater activation medium (P < 0.001), such that the percentage of eyed embryos declined across the pre-incubation time gradient. Activating medium had a significant effect on the percentage of eyed embryos for each pre-incubation time (P < 0.05). More precisely, freshwater produced the lowest percentage of eyed embryos at all pre-incubation times, whereas saline water and Woynarovich solution produced the highest percentage of eyed embryos at 0 s and 30 s before incubation. Examination of sperm traits showed no impact of activating medium on computer assisted sperm analysis parameters. Our results suggested that saline water or Woynarovich solution improve fertilization rate in Ide during fertilization. In conclusion, this thesis provides basic knowledge on gamete biology, role of egg receptivity period, effects of pre-incubation of eggs and different activating medium which can be useful to understand the fertilization strategies of different externally fertilizing fishes as well as standardize their fertilization protocol for captive reproduction.

Vliv teploty vody a intenzity světla na raný vývoj sumečka afrického v komerčním chovu
PROKEŠOVÁ, Markéta
The successful production of quality early fish stages is crucial for artificial rearing fish species. Nevertheless, it is quite a problematic process, because fish as poikilothermic organisms are highly sensitive to various environmental conditions. Moreover, both fish embryos and larvae are more affected by biotic and abiotic factors (such as predation, stocking density, temperature, light, pH, salinity, oxygen saturation, feeding availability, or their interactions) than older juveniles or adults. Most fish processes such as reproduction, metabolism, survival, development and growth can be considerably (positively, negatively or not) influenced by these conditions. Therefore, it is important to understand their impacts on fish stages during embryonic, larval, juvenile, adult, and eventually the senescent period. Then, following the application of new knowledge to the practise, especially species- and age-specific optimal conditions, should result in higher survival, better growth rate, well developed fish without deformities and lower cannibalism. The objectives of the present thesis were to assess the effect of water temperature and light intensity on the early development (embryonic and larval period) of African sharptooth catfish as a perspective fish species for freshwater intensive aquaculture. Due to its great characteristics (for instance fast growth, ability to breathe atmospheric air, rearing at high stocking density) this species can meaningfully contribute to the global aquaculture production which is expected to rise in the coming years. However, there are still some difficulties in the early rearing African sharptooth catfish regarding the cannibalism, feeding, survival and necessity of detailed information about the effects of some abiotic factors and their interactions.

Inovativní metody v chovu a reprodukci candáta obecného (Sander lucioperca)
BLECHA, Miroslav
The whole Ph.D. thesis includes in total 10 chapters on 146 pages. Chapter 2 9 are specific parts of thesis where following scientific and practical aspects of pikeperch reproduction biology and aquaculture are described. Quality and quantity of pikeperch spermatozoa after varying cold water treatments are presented in the chapter 2 and can help to optimize broodstock management of males with the aim to obtain high quality spermatozoa during a seasonal and an out of season spawning as well. Benefits of hormone treatment of both sexes in semi-artificial reproduction in pikeperch are described in the chapter 3 where the importance of hormonal treatment of both sexes in tank spawning is evaluated for effective production pikeperch larvae. The use of an alcalase treatment for the elimination of pikeperch egg stickiness is being shown in the chapter 4 of this thesis. Post-ovulatory oocyte ageing and its effect on eggs viability rates and occurrence of larval malformations and ploidy anomalies are listed in chapter 5. These results describe the effects of the egg over ripening fertilization process in pikeperch. The first report of heat shock triploidisation in pikeperch is described in chapter 6 with production of 100% pikeperch triploid population. The effect of water surface treatment on survival, swim bladder inflation and growth of larvae is given in the chapter 7 with the aim to optimize the intensive culture of pikeperch larvae. Last two chapters (8 and 9) are describing the adaptation of intensively cultured juveniles to pond culture and the adaptation of pond-cultured juveniles to RAS as a new and effective methods for ongrowing production of pikeperch. In total, four published scientific papers, one handbook, one accepted scientific paper for publication, and two prepared scientific manuscripts are included and discussed in this Ph.D. thesis.

The use of (nano)oxides for metal and metalloid stabilization in contaminated soils
Michálková, Zuzana ; Komárek, Michael (advisor) ; Luke, Luke (referee)
The main objective of the thesis was to evaluate the potential of selected Mn and Fe (nano)oxides for the stabilization of metals and metalloids in contaminated soils. The research was focused basically on three materials - commercial nanomaghemite (Fe III), nanomagnetite (Fe II,III) and a synthetic amorphous Mn oxide (AMO). The main aim of the work was to provide a complex view on the chosen stabilizing amendments regarding not just their direct influence on contaminants mobility and stabilization mechanisms, but also their stability and alterations in soil conditions together with influence on soil microorganisms and higher plants. Firstly, adsorption properties of the tested materials towards Cd, Cu, Pb and As were investigated. In this context, the most effective material showed to be the AMO reaching one to two orders of magnitude higher adsorption capacities than Fe III and Fe II,III under given experimental conditions. Interestingly, the rate of As(V) adsorption onto AMO was increasing with increasing pH as a result of high pHzpc of the AMO (8.1) and significant dissolution of this phase at lower pH values. As a next step, the influence of (nano)oxides on metal(loid)s mobility and other physico-chemical soil characteristics after application to contaminated soil was examined. Again, the AMO proved to be the most efficient in reducing mobile pools of Cd, Cu, Pb, Zn and As. On the other hand, Fe III and Fe II,III addition had generally less significant effects on contaminants mobility. AMO application further resulted in an increase of soil pH connected with AMO dissolution and unwanted decomposition of soil organic matter. When (nano)oxides alterations in soil conditions were observed, MnCO3 coatings were identified on AMO surface while no significant changes were recorded for Fe III and Fe II,III. As the MnCO3 formation was connected with increased AMO stability, AMO particles synthetically covered with MnCO3 coating (denoted as SM AMO) were prepared. Although the SM-AMO had a lower mass loss in soil than pure AMO, the stabilizing efficiency was almost the same for both materials. The differences in surface composition of both materials were decreasing with time as MnCO3 naturally precipitated on the AMO surface in soils while the SM AMO coating was gradually dissolving. When investigating the effect on soil microbiota, AMO efficiently promoted soil microbial activity while no significant changes were observed in the case of Fe III and Fe II,III. The AMO was also able to reduce the uptake of Cd, Pb and Zn by sunflower (Helianthus annuus L.), eliminate Zn phytotoxicity symptoms and increase biomass yield. On the other hand, toxic levels of Mn released from the AMO in an acidic soil were found in sunflower tissues. AMO application is thus recommended for contaminated neutral or slightly alkaline pH with a higher cation exchange capacity in order to avoid unwanted release of Mn. Finally, various types of AMO-biochar composite sorbents were recently prepared and field experiment focused on stabilization of Cd, Pb, Zn and As using studied materials is currently under preparation. The combined results from the thesis highlight the importance of a complex experimental approach dealing with all parts of the contaminated soil environment in order to obtain complete information about the efficiency and usefulness of any newly developed stabilizing amendment.

Effect of sex on growth and formation of dorsal muscle of pigs
Fáberová, Gabriela ; Čítek, Jaroslav (advisor) ; Zadinová, Kateřina (referee)
Effect of sex on growth and formation of dorsal muscule of pigs Summary The aim of this thesis is to determine the influence of gender on the growth and formation of the pigs dorsal muscle. Growth is one of the basic phenomenon characterizing living organism. Is a creation of nonliving to living matter. The amount of body mass is not constant through the life, it is changing significantly. In the early postnatal period is skeleton growing faster compared to muscles and fat then leads to faster growth of muscle and in the last period called maturity to the fattening. Evaluating growth has a significant gender effect. In case of pigs, it is common to feed barrows and gilts. Nowadays it begins to think about feeding of boars or the imunocastrates. Due to different hormonal activities we can expect different muscle and fat deposition. The task of this study was to clarify the influence of gender on the formation and growth of pigs dorsal muscle. There were 72 pigs tested in total. Pigs were housed in pairs in cotes and divided by gender for pigs, boars, imunocastrates and sows. This subpopulation of genotype DanBred animals were divided to 1/4 (18ks) uncastrated male pigs (K) 1/4 (18ks) hormonally castrated male pigs (I), 1/4 (18ks) barrows (V) and 1/4 (18ks ) gilts (P). Average live weight of pigs at the start of the trial was 28.5 kg, while the test was conducted to average 107 kg bodyweight. Through all time pigs were fed ad-libitum KKS. During the test it was monitored at weekly intervals individual live weight, back fat thickness at A, B, muscle depth at A, B and the total percentage of muscle for all categories of pigs. The obtained results show that the growth and formation of a long dorsal muscle are influenced by gender. When comparing the weight in a given period, we conclude that during the time the difference between gilts and imunocastrates grow up. Best growth had imunocastrates gilts similarly, only was there an earlier stop of the growth. The highest increase in fat and muscle measured at the A and B, occurred in pigs, in sows we can see increasing gains in fat with respect to the period in which they are fattening. Boars had the lowest backfat thickness, imunocastrates. With imunocastrates we evaluate low fat increase compared to the beginning of the observation. The biggest muscle depth measured at A and B had the barrows with gilts and imunocastrates and especially boars did not reach the values as barrows and gilts, who had the highest muscle depth. Biggest % of muscle was measured in sows. A large proportion of muscle can be seen in male pigs. The proportion of muscle mass of imunocastrates was under the average and worst ratio of muscle had especially at the end of feeding barrows indicating that with increasing age there is a significant fattening, compared to the remaining groups of pigs Keywords: pig, growth rate, muscle fibers

The influence of time in feed enrichment with unsaturated fatty acids to selected parameters of pig carcass value with regard to the fatty acid composition of intramuscular fat
Pantoflíček, Jiří ; Čítek, Jaroslav (advisor) ; Miloslav, Miloslav (referee)
The thesis aims to evaluate the impact of aliment with higher contents of unsaturated fatty acids, consumed for a different period of time, to utilitarian attributes of pigs before a slaughter, with respect to the composition of fatty acids in the intramuscular fat of tested animals. The factors that influence the quality of meat are interior, exterior and technological. Among the qualitative markers of quality of meat we rank the share of meat and fat, acidification rate, color, viscosity, contents of intramuscular fat (marbling), smell, taste, juiciness and delicacy. Together with hygienic and nutritive attributes, consumers and processors consider these technological and sensory aspects to be the most important. The ultimate goal of this thesis is to compare the impact of different length of feeding soy oil on parameters of pork meat quality and growth. However, the interference of growth attributes was inconclusive and the test result came similar in different groups of tested pigs. What was influenced by adding the soy oil into the feed is the fatty acids profile. The contents of fatty acids remained unchanged in every test group. Over time the content of monounsaturated fatty acids decreased. The most significant change occurred in representation of polyunsaturated fatty acids, which increased in the test groups with longer period of feeding with enriched feed, mostly at the expense of monounsaturated fatty acids. The differences between the test groups of pigs were statistically inconclusive; therefore the soy oil enrichment did not worsen the technological parameters of meat and fat quality. The longer period of feeding the soy oil enriched feed led to significant increase in polyunsaturated fatty acids. According to the findings, adding the soy oil into the feed will have no effect at all if done short time before the slaughter.

Analysis of biological features of Capsella bursa-pastoris (L.) Med.
Schneebergerová, Tereza ; Hamouz, Pavel (advisor) ; Holec, Josef (referee)
The aim of this bachelor thesis is to determinate selected biological characteristics of shepherd´s-purse, which have impact on the establishment and expansion of its populations in field crops. In particular, development of primary dormancy was studied and the effect of factors that influence the dormancy and germination of seeds was determined. Shepard´s purse is an annual or biennial herb of the cabbage family, which is classified as winter annual weeds. Primarily infest the winter and spring crops, rapeseeds, potatoes or forages. It appears from lowland to foothills, so biological features of individual population can be very different. The ways of control are shallow tillage or herbicidal treatment. After harvesting of ripe seed the first experiment was set to define the primary dormancy. Remaining seeds were stored in two different types of environment. Part of seeds was stored in the dry at 20 °C. Others seeds were stratified at 5 °C. Effect of storage conditions on primary dormancy was tested every two weeks. Seeds were germinated for 1 week in grow chamber under the influence of various factors such as different light mode, type of water and type of media for germination. The results were processed by multiple-factor analysis of variance. Fresh seeds showed a strong primary dormancy at constant temperatures of 10 °C and 20 °C. Treatment with fluctuating temperature (20/10 °C), filter paper, drinking water and stored in dark had the highest germination rate (10.75 %). Seeds stratified at 5 °C had increase in germination in first weeks, but lost it during storage. On the other hand, seeds stored in dry at 20 °C firstly were in dormancy, but they lost it gradually during storage.

Analysis of sheep utility attributes in ecological and conventional flocks in the Czech Republic
Linhartová, Iveta ; Ptáček, Martin (advisor) ; Jan, Jan (referee)
The goal of this diploma thesis was to perform an analysis of sheep breeding of Suffolk breed in basic reproductive performance and meat production traits aspects. The information for rating these aspects was used from two farms. The first of them used conventional way of breeding (ZVOZD Horácko, družstvo) and the second one used ecological way (EkofarmaKosařůvmlýn, s.r.o.). Fertilization, fertility, intensity and rearing belong among monitored reproductive indicators. These reproductive indicators are expressed in percentages. Regarding meat production traits rating in this thesis we compared influences of year of lambing, farming method, birth month, sex, litter size and age of dam. All these influences were judge according to birth weight (kg), weight at the age of 100 days (kg), average growth (g), depth of the longest dorsal muscle (mm) and according to depth of subcutaneous fat (mm). Reproductive performance and meat production were monitored in years 2011, 2012, 2013, 2014 and 2015. In terms of reproductive performance with a few exceptions it was true that ZVOZD Horácko, družstvo reached the best values, and in most cases better than the national average. For example in terms of intensity values in 2012 ZVOZD Horácko, družstvo had 35,9% better results compared to national average. In the same year this farm reached 48,1% higher values of percentage rearing compared to national average. Ekofarma Kosařův mlýn, s.r.o. showed worse performances, however it was in most cases better than national average. In terms of intensity in 2011 Ekofarma Kosařův mlýn, s.r.o. had the same results as the ZVOZD Horácko, družstvo. Meat production properties were supported by statistical calculations and all of them were conclusive at least at the level of significance P < 0,05 in all cases except month of birth effect on birth weight. The best results of meat production in terms of effect of lambing had the year 2012, when the birth weight was one of the highest and the other properties (weight at the age of 100 days, average growth, depth of the longest dorsal muscle, depth of subcutaneous fat) were by far the highest in the period of 2011-2015. Next we found out that the ecological way of breeding (in this case Ekofarma Kosařůvmlýn, s.r.o.) has better results than the conventional way (ZVOZD Horácko, družstvo). The effect of birthmonth has the significant influence on the indicators of meat production and the lambs born in April had the best results. In the case of sex rams are better. Litter size has very important influence on meat production the more lambs per one mother, the lower birth weights, the lower weights until the period of weaning, the lower weights at the age of 100 days. It is affected by milkiness of the mother. Moreover, the age of mothers also play a significant role. In our research the highest birth weights had lambs of one year old mothers and all other indicators were the highest in the case of three year old dams.

Characteristics important for ensuring of sustainable and development of dairy cattle herds breeding
Lelek, Jaroslav ; Stádník, Luděk (advisor) ; Petr, Petr (referee)
The aim of this dissertation was to assess the influence of characteristics important for ensuring of sustainable and development of dairy cattle herds breeding. The data investigated describe approximately 5138 dairy cows in period of four years in selected farming´s of dairy cattle in district of Jičín. There were these indicators of reproduction processed: conception rate after first insemination, conception rate after all inseminations, interval of insemination, index of insemination, service period and meantime; the data were collected from seven stables of Bohemian Spotted cattle and from seven stables of Holstein cattle. The longevity was investigated from the number of dairy cows at respective lactation of both investigated breeds and from the average lactation in respective years. The results of investigation prove that the average percentage representation of dairy cow at respective lactation between 2012-2015 ranged 33,4 % at first lactation, and 24,68 % at second lactation, and 18,13 % at third lactation, and 11,48 % at fourth lactation, and 6,53 % at fifth lactation, and 3,32 % at sixth lactation, and 2,36 % at seventh and more lactations. The evident data from comparison prove, that till third lactation there is higher percentage representation of Holstein cattle and from third lactation there are more cows of Bohemian Spotted cattle, and also the average reached lactation confirms this the value of 2,75 lactation for Bohemian Spotted cattle and the value of 2,3 lactation for Holstein cattle. The influence of breed on the average length of lactation was quite weak. The results of rating indicators of reproduction also have not proven any statistically important difference between both types of cattle as concerns values reached by each cattle, but the original Bohemian Spotted cattle reached better results in all indicators, and thus it is probably more suitable for the area of district Jičín.

Hygienic safety of outdoor playgrounds with sandbox
Abertová, Jana ; Borůvka, Luboš (advisor) ; Anna, Anna (referee)
Playgrounds represent danger of a direct input of hazardous substances into children`s organism, that`s why they require a special attention. The diploma thesis deals with hygienic safety of outside playgrounds with sandpits in scope of valid legislation and medical risks, which might be caused by contamination. The aim of the thesis is to assess the level of microbiological, parasitical and chemical contamination and hygienic safety of sand in outside playgrounds with sandpits in Hradec Kralove. To check the contamination, samples of sand were taken in outside playgrounds with sandpits destined for children in Hradec Kralove. Safety parameters of taken samples were rated according to notice No. 238/2011 Coll., about setting of hygienic requirements for swimming pools, saunas and hygienic limits for sand in sandpits of outside playgrounds. The evaluation of samples was concentrated on microbiological, chemical and parasitical contamination of sandpits, which was analyzed by Medical Institute based in Usti nad Labem. The influence of position of playground within the town (city center vs. outskirts), time of collecting samples and age of each sandpit were judged. The sandpits in Hradec Kralove in the years 2014 and 2015 were microbially contaminated over established limits only in one case. Parasitical or chemical contamination was not found in any case. Next conclusion is that sandpits at end of season are contaminated by microorganisms about 18 % more often than at start of season and at the same time that sandpits in city center are contaminated about 14 % more frequently than in outskirts. New sandpits are often contaminated by thermotolerant coliform bacteria than old sandpits. From the point of view of chemical contamination, sandpits in city center are more contaminated by chemicals, however statistical difference is not significant. The discovered values of sand at start and end of season were misrepresented by addition of sand in sandpits in the course of main season. Sandpits in Hradec Kralove had a high level of hygienic safety, which is determined in law No 258/2000 Coll., about protection of public health.