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Populatio analysis sheep breeds included in the gene resources in the Czech republic
Benešová, Jaroslava ; Vostrý, Luboš (advisor) ; Karel, Karel (referee)
Genetic variability reflects the degree of diversity of the population breeds of livestock and seed objectives can greatly decrease. As a result of the reduction of the genetic variability of the population experiencing adverse effects or to the complete extinction of the breed. Adverse effects are manifested primarily on the fitness of animals and their commercial properties. When sufficient population size and when are these influences mating panmictic minimum, however, in populations where there is a reduction in the number of individuals, these effects are essential. In connection with inbreedingem is acting negatively influences called inbred depression. The degree of inbreeding in populations is necessary to monitor and on the basis of creating mating plans, so that was the greatest genetic gain achieved in the conservation of genetic variability, which will have a negative effect on fitness and utility properties.
Population analysis was prepared based on data from the herd-books in 1985 up to 2013. The data contained the pedigree of the Bohemian Forest sheep, which is placed between the genetic resources in the Czech Republic. Using the program SAS 5.8 (Statistical Analysis Software) the value of the coefficient of inbreeding have been established for each individual and the average value of the entire population. The other trend was the evaluation of the parameters of the vyhodnocenými coefficient of inbreeding in the reference period and the effective population size, and the generational interval for the four paths of transmission of genes and two transmission paths of genes. The trend of development of the coefficient of inbreeding (Fx) was evaluated as a kolísavě rising with an average of around 0.6%. The average generation interval (L) for the four paths of gene transfer was calculated for two years and 3.83 journey 3.55 years gene transfer.
The value of the generation interval, the shorter the period considered, resulting in the intensification of genetic gain. The effective population size (Ne) was estimated in two ways. The total effective population size (Ne) taking into account the kinship was estimated to number of 85 individuals and effective population size involving only males and females was estimated at 3070 individuals. On the basis of the analysis of the coefficient of inbreeding, the generation interval and effective size of the population it is possible to sort the sheep from the Šumava with the low degree of coefficient of inbreeding and the average generation interval. On the basis of the value of effective population size 85 individuals may be experiencing the sheep breed known as endangered.
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The negative effects of inbreeding in wild animals
Podhajecká, Iva ; Hofmanová, Barbora (advisor) ; Vostrý, Luboš (referee)
This bachelor thesis first explains the term of inbreeding itself, it also presents various definitions and patterns of inbreeding, that allow to determine the degree of inbreeding in an individual. Then it describes ways, in which inbreeding impacts population allele frequency and other effects influencing populations (e.g. Bottle-neck Effect, Founder Effect or Genetic Drift). Inbreeding is undesireable in nature, because it leads to inbreeding depression. That manifests itself by decreasing individuals fitness, which then has a substantial impact on populations dynamics. Main part of the thesis is then focused on wild populations of birds and mammals. The degree of inbreeding is most commonly assessed by pedigree analysis. That is a highly demanding method, as it requires a longterm population observation in the field and, in many cases, also tissue collection for genetic analysis. The last step is represented by thorough statistical analysis, allowing to determine kinship in population as precisely as possible. Based on pedigree, we can calculate coefficient of inbreeding 'F', which then allows us to determine the extent of inbreeding depression. The last part of the thesis describes effects of inbreeding on offspring fitness, reproductive success and immunity in avian and mammal populations. As each of the populations has different specifics, the base characteristics of a particular population are described first and then the impacts of inbreeding on individual fitness indicators are presented. As opposed to populations living in captivity, wild populations are adversely affected by other factors, mainly environmental, that can deepen inbreeding depression. Studies dealing with these issues are therefore extremely important, as their findings can be applied into improving of management and conservation of endangered species.
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Reproduction of domestic horses (Equus caballus): The effects of inbreeding, social environment and breeding management
DUBCOVÁ, Jana
This thesis is focused on horse social behaviour and reproduction under human management. First part of the thesis covers issues about reproduction influenced by humans, breeding in restricted areas and artificial processes which can interfere or threaten the domestic horse population survival. These issues are described in lifetime order from conception, through lactation and maternal investment up to weaning, and on the background of detailed information about particular individuals. The second part is focused on social interactions and forming dominance hierarchy within the groups of domestic horses.
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Breeding Results of Bohemian Red Cattle in South Bohemia Region
VAŇKOVÁ, Kateřina
This work is focused on the evaluation of breeding Czech red cattle breeders working South Bohemian Region, guaranteed of the Faculty of Agriculture, University of South Bohemia in České Budějovice. This work describes the characteristics of the breed, its origin and the process of regeneration. The ongoing process began with the absorptive crossing of Czech Pied cattle with Czech red bulls, which led to the increase of female part of population over the number corresponding with the size of critically endangered breed. The situation in male part of population is less favourable with critical lack of bulls, which slows down the regeneration process. According to the exquisite assumption of meat production, but with worse results of milk efficiency, the breeding of cows without market milk production seems to be the best way. It is very important to keep of safe boundary of koeficient intensity of family breeding at potential descendants. Not even providing this process to be successful, the breeders Czech red cattle won{\crq}t get along without adequate subsidies, which should be offer to partial animals with verified genotype according to their category. Currently is the number of animals with genotype CC, which fall under the control of appointed department, 114 pcs.
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