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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Trestněprávní aspekty asistované reprodukce / Criminal aspects of assisted reproduction

Paták, Milan January 2013 (has links)
The concept of assisted reproduction is widely discussed by both professional and lay public. New scientific discoveries in the fields of biology and medicine as well as the use of methods and procedures that enable the emergence of new life raise number of issues, not only the legal ones. The purpose of this thesis is to provide the comprehensive survey of criminal law relationships which may arise in the context of providing the assisted reproduction. The thesis examines whether the current legislation guarantees sufficient protection of relations, interests and values covered by the Criminal Code. Within the analysis of crimes the thesis deals with the need for criminal repression and gives proposals de lege ferenda. The thesis is composed of five chapters. The first chapter is subdivided into two parts. Part One defines the concept of assisted reproduction, describes the historical overview of the events that preceded the current interpretation of the concept and explicates basic medical terminology related to the chosen topic. Part Two presents the basic principles on which the Czech regulation is established and contains specification of the relevant sources of law. The second chapter briefly characterizes the criminal and medical law and clarifies their relationship. The third chapter deals with the...
102

Faktory ovlivňující reprodukční ukazatele dojnic ve vybraném chovu

ZERZÁNKOVÁ, Veronika January 2019 (has links)
This thesis provides an overview of the literature on reproduction attributes of the Holstein Friesian cattle and its influence on the cattle reproductive indices. One of the goals was to evaluate the influence of selected factors on the reproduction indices for a pre-selected group of dairy cattles. The data has been processed and sorted by the lactation production levels, daily production, order of lactation and the age of the first calving. The data about the used bulls has been processed as well. Another goal of the thesis was acquisition of the data about excluded cows. For the excluded cows, the age, order of lactation, reason for exclusion and life-long production have been recorded. The data for the thesis have been obtained from the production control records and database of breeds in the selected Holstein cattle breeding. The dairy cattles, which got in calf during the years 2017 and 2018 have been evaluated. In particular, for 2017 and 2018, the evaluation was carried out on 190 and 229 dairy cattles respectively, which makes the total of 419 evaluated cows. For those dairy cows, the insemination index data, insemination interval, gestation after first insemination, service period and gestation period has been recovered from the zootechnical register. The evaluation of excluded dairy cows contained 339 dairy cows, which have been excluded during years 2017 and 2018. For the evaluation of the used bulls, the total count and description of how the bull for insemination have been selected is provided. Evaluation the influence of level of lactation production on the reproduction indices has shown a significant (p0,05) statistical relation between production levels and duration of the service period. It has also been proven that this has an influence on the insemination index levels. The lowest values (p0,05) of service period and insemination index have been detected for dairy cattles with production up to 6 999 kg. On the other hand, the highest values of service period and insemination index have been recorded for the dairy cattles with production up to 9 000 kg (p0,05). The influence of daily dairy production levels on the reproduction indices have been evaluated as well. It can be clearly seen from the results that as the daily dairy production increases, the service period increases as well. The lowest values (p0,05) of the service period was recorded for breeds, who had the daily production levels up to 24.99 kg. Opposed to that, the highest values of service period have been recorded for dairy cattles with average daily milk production over 30 kg. The evaluation of order of lactation on the reproduction indices did not show any significant statistical results (p0,05). Furthermore, during the evaluation of first calving, no statistically significant differences have been shown (p0,05). Last reproduction index we have evaluated was gestation after the first insemination. The groups were divided by the production levels, daily milk production, order of lactation and age of the first calving. For each group, the percentage of cattles that got in calf after first insemination has been computed. On average, this value was 36.28%.
103

Ekonomické vyhodnocení reprodukce u populace masného plemene Aberdeen Angus

JUNGWIRTH, Václav January 2019 (has links)
The aim of the thesis was to evaluate the influence of reproductive indicators on the economy of cows depending on the 1st calving of heifers. In the set of cows were comapred the costs of heifers rearing up to 1st calving, longevity costs, sales and costs of weaned calves, and complete result of economy in the groups.
104

Ekonomická analýza plodnosti u stáda dojeného skotu

MAČLOVÁ, Jaroslava January 2019 (has links)
The aim of the work was to evaluate the milk production and fertility of the herd of Czech piebald cattle and to express the economic impact of the use of various breeding bulls used for breeding. The results of milk yield and insemination were evaluated in the years 2017 - 2018 for the last closed lactation sequence in the groups according to the order of lactation (1st lactation, 2nd lactation, 3rd lactation, 4th and next lactation). The indicators were evaluated for the three most commonly used breeding bulls. The average efficiency by the lactation sequence was in the 1st lactation 5143 kilogrammes of milk (P 0.001), the 2nd lactation 6520 kilogrammes of milk (P 0.01), the 3rd lactation 8186 kilogrammes of milk (P 0.001) and in the 4th and next lactation 7855 kilogrammes of milk. The efficiency of the whole herd was 6856 kilogrammes of milk contains 4.09% of fat and 3.46% of proteins. The avarige age at the first calving was 945 days, the length of the herd´s interval was 416 days, the insemination interval was 93 days and the service period was 129 days. The success rate of the 1st insemination in 2017 was 75%, in 2018 74%. The success rate of all insemination was 69% in both years. The costs of insemination of the whole herd with using all bulls in 2017 was 618 CZK and in 2018 was 577 CZK. Was found economic difference in using individual breeding bulls included in reprodudtion in a given herd.
105

Vyhodnocení reprodukce v chovu ovcí clun forest

KLEČÁKOVÁ, Martina January 2019 (has links)
The aim of the diploma thesis was to evaluate reproduction indicators (percentage of pregnancy, fertility, intensity, total rearing, reactivity, rearing of lambs born and total lamb mortality), their comparison over the years and the average in the Czech Republic. The influence of the age of the mother on fertility and the proportion of sheep according to the frequency of litters was also evaluated. Monitoring was carried out in breeding sheep clun forest (at 30 ewes) at Studnice farm from 2015 - 2018. In the monitored reproduction indicators, there was a statistically significant effect (P 0,01) only in the fertility of the herd in question for the period 2015 - 2018. This was caused by higher fertility differences in the first two years on average by 10% between selected breeding and average in the Czech Republic . For the past two years, fertility was on average 25% lower than the national average. When assessing the effect of maternal age on fertility, the highest fertility rates were in three-year-old (174%) and four-year-old sheep (168%). The effect on the highest fertility rates was the highest number of lambs born (about 2 lambs per sheep). Since the third year of age fertility has fallen until the fifth year. Then there was a slight increase (the number of born lambs in the sheep (1.5 lambs) increased) and the lowest fertility (133%) was found in seven-year-old and older sheep, when the number of lambs was also decreasing. Based on the above data on the effect of age on fertility, a statistically highly significant effect (P 0,01) was observed in the observed breeding for the years 2015 - 2018.
106

Vliv maedi-visna viru na reprodukční ukazatele ve vybraném chovu plemene šumavská ovce

OUŘEDNÍKOVÁ, Kateřina January 2019 (has links)
The aim of the thesis was to evaluate the influence of maedi-visna on reproductive indicators in selected Šumava sheep breeding. Serological test ELISA was accomplished in the evaluated herd, and its results were used for comparing reproductive rates of healthy and infected ewes. Maedi-visna disease was proved in 16 out of 193 samples (8, 29 %). Statistically significant influence of maedi-visna was shown in indicators such as age of infected ewes and number of reared lambs. For other indicators (number of live birth lambs, lambs weight in 100 days, occurrence of sterility, mortality and stillborn lambs) higher success rate was observed in maedi-visna negative ewes, however these findings were not statistically significant. Maedi-visna is incurable disease and most important tool how to avoid this disease is preventive protection of the sheep breedings.
107

Vybrané vlivy na reprodukci plemenic holštýnského skotu

ŠPAČKOVÁ, Vladislava January 2019 (has links)
The work deals with the evaluation of selected effects on reproduction of Holstein cattle breeds. The aim of the study was to evaluate reproductive parameters (insemination index, insemination interval, period service, interim, pregnancy after the first insemination) in a selected group of dairy cows. These reproductive indicators were subsequently evaluated depending on genotype, performance level, lactation order and age at first calving and used synchronization methods. The evaluation took place at the Vřesce farm, belonging to company Rynagro a.s. 260 Holstein breed cows and their hybrids were included. The results showed that some reproductive indicators (insemination interval, service period and interim) of the monitored group of dairy cows were lower than the average of the Czech Republic. When evaluating the genotype effect on reproductive parameters, a highly significant effect (p<0.01) of genotype on insemination interval was found. Holstein breed cows had a 7-day higher insemination interval than other crosses. In evaluating the effect of daily milk yield was not proven statistically significant differences (p>0.05) in period servis and interim. Statistically significant differences (p<0.05) in insemination index, insemination interval and pregnancy after the first insemination were proven in the performance evaluation. The p-value of the global null hypothesis was close to 0.05 and no significant differences between the compared groups were demonstrated in the subsequent multiple comparison. The effect of the order of lactation on reproductive parameters was not proven (p>0.05). However, interesting results were found by the impact of age at first calving. There was a statistically highly significant difference (p<0.01) between the groups in the insemination interval and the interim and a statistically significant difference (p<0.05) between the groups in the service period. Cows with a first calving age 23 months had all of these indicators lowest, the highest values were found within cows with a first calving age of 28 months. After evaluating the correlation analysis, a significant effect of age at first calving on insemination interval (p<0.05; r=0.13), on interim (p<0.01; r=0.17) and period service (p<0.01; r=0.17). Synchronization methods were used in 125 cows and the overall success rate after this treatment was 47%. The most commonly used protocol was the Ovsynch method. The calculations based on the extension of the service period quantified the theoretical loss for the extended cycle of dairy cows. This loss is 7 030, - CZK per cow and takes into account the losses for milk and the unborn calf, not the cost of further insemination and treatment of cows.
108

Právní problematika zárodečných buněk ve vztahu k asistované reprodukci / Legal issues of gametes in relation to assisted reproduction

Stieranková, Aneta January 2019 (has links)
66 Abstract Legal issues of gametes in relation to assisted reproduction The thesis deals with the issue of assisted reproduction with a specific focus on gametes and some issues that are associated with them. In order to better understand contradictory opinions and views on a particular issue, the Czech legislation is compared with the British legislation. Then, in each individual case, it is assessed which country has dealt with the problem better, using a comparative method. The introduction of the thesis deals with assisted reproduction in general, especially from the point of view of definition of the concepts and historical development of this issue. Subsequently, the basic legal framework for assisted reproduction is defined both in the Czech Republic and the United Kingdom. Briefly, there are also summarized the most basic requirements for gametes donors in both countries. In terms of specific problems related to gametes, much of the work focuses on the anonymity of sperm donors, in particular summarizing the most important arguments of its opponents and subsequently refuting these arguments. The conclusion of this chapter submits why, in my view, the anonymity of sperm donors should be maintained. The next part is devoted to financial rewards for donation of gametes, their admissibility and amount....
109

Ekonomické souvislosti současného reprodukčního procesu obyvatelstva ve světě

Zozulynets, Lidiya January 2007 (has links)
První kapitola je věnovaná současnému vývoji světové populace a jeho dopady na světovou ekonomiku. Další část je zaměřená na reprodukční proces obyvatelstva ve světě. Třetí část je věnována vývoji porodnosti v rozvojových ekonomikách. Zde jsou podrobněji rozebírány nejproblematičtější regiony Afriky a Asie. V Poslední části je analyzoán vliv ekonomických faktorů ovlivňujících klesající přirozený přírůstek obyvatelstva v rozvinutých zemích.
110

Manipulace zárodečných buněk jako nástroj pro management a produkci izogenních linií u ryb

FRANĚK, Roman January 2019 (has links)
Isogenic lines in fish represent a fundamental approach to control the genetic background of experimental animals. All individuals from a given isogenic line share the same genotype. So far, isogenic fish lines have been produced only by repeated uniparental inheritance - androgenesis and gynogenesis. Homozygous progeny is produced in the first generation of uniparental inheritance, and each homozygous individual produces a different isogenic line after second generation of uniparental inheritance. Despite optimized procedures for inducing uniparental inheritance, isogenic lines have been successfully produced in only a few species of fish. Doubled haploids after first uniparental inheritance have affected fitness as well as reproductive performance. Long-term maintenance is considerably problematic even when isogenic line is established already, due to low viability and poor reproductive characteristics. The situation is further complicated by the fact that isogenic lines are usually naturally monosex, thus uniparental inheritance must be re-used for further reproduction, or sex reversal needs to be applied in part of isogenic line. Several types of germ cell manipulation were performed in presented thesis. Protocols for cryopreservation of spermatogonia and oogonia have been developed and optimized to maximize post-thaw viability. The physiological activity of cryopreserved cells was confirmed by transplantation into a surrogate host. Cryopreserved and subsequently transplanted cells retained colonization activity comparable to non-frozen control germ cells. More importantly, male germ cells were able to transdifferentiate from oogonia. The success of transplantation was confirmed by detection of expression of genes associated with gametogenesis in carp by RT-PCR. In the next study, the results of cryopreservation experiments were followed, where sterile goldfish was identified as a suitable host for homozygous carp cells. Germ cells obtained from several homozygous individuals were individually transplanted into sterile goldfish. This procedure has a potential to increase the chance of producing a viable gamete for isogenic line production. Germ cells from homozygotes with affected gametogenesis can be transferred to fully viable recipients, thereby increasing the efficiency of isogenic line production overall. In addition, the use of a goldfish as a surrogate parent will ensure that part of the germline chimeras will be male and female, thus isogenic gametes of both sexes can be obtained and no further intervention for further reproduction of the isogenic line. The suitability of triploid zebrafish, which can potentially be used as recipients for cells from homozygotes to produce isogenic lines, has been confirmed for zebrafish. Spermatogonia and oogonia from diploid donors were transplanted into artificially induced triploid larvae. Donor-derived sperm was were obtained upon maturation of triploid recipients. Transplanted oogonia transdifferentiated into spermatogonia and spermatozoa with female sex chromosomes have been produced, which may be of interesting for further studies of sex determination in zebrafish. A new germline transfer technique has been developed using striped embryos. Donor cells were transplanted from the blastula stage to the swim-up larvae. With this approach, undifferentiated primordial germ cells were able to colonize the genital groove and initiate gametogenesis. After reaching sexual maturity, germline chimeras were obtained with gametes and viable progeny. Although the overall efficacy of this method was lower compared to other transplantation methods, this study may be of relevance for germline rescue in poorly viable embryos or lethal mutants.

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