National Repository of Grey Literature 30 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Proteomic architecture of sperm-egg interactions
Otčenášková, Tereza ; Stopka, Pavel (advisor) ; Petr, Jaroslav (referee) ; Vrbacký, Marek (referee)
Recent advances in proteomic methods provide new insights for biological research including the field of reproductive biology. Determination of the proteomic basis of spermatozoa is pivotal for understanding the complex process of gamete interactions during fertilization such as acrosome reaction. Great differences imposed by postcopulatory sexual selection and phylogeny can be observed regarding the size, shape, and molecular composition of sperm across animal taxa. The first objective of this doctoral thesis is to characterize the protein contents of the acrosome to ascertain its further functional significance in sperm-egg interaction. Also, we aim to investigate the potential relationships between sperm protein composition and sperm morphology diversification, risk of sperm competition, and species phylogenetic background. Wild-caught males from natural populations of species of Mus musculus musculus, Apodemus flavicollis, Microtus arvalis (order Rodentia), Acrocephalus palustris, Chloris chloris, Phylloscopus collybita, Cinclus cinclus, Hirundo rustica, and Taeniopygia guttata from a captive population (order Passeriformes) were subject to the analyses. Nano-liquid chromatography with tandem mass spectrometry was applied as the main methodological approach in this thesis. Our data implicate...
Use of animal models in Leishmania research
Pekařová, Julie ; Vojtková, Barbora (advisor) ; Pacáková, Lenka (referee)
Leishmaniasis is a disease caused by parasitic protozoa of the genus Leishmania, whose life cycle includes a mammalian host and an insect vector, typically of the genus Phlebotomus or Lutzomyia. While the number of vectors is limited, the spectrum of hosts is wide. Therefore, there are also many animal models that can be used for the study of different aspects of leishmaniasis. These include the study of the host's immune response, pathological manifestations of diseases, virulence factors or testing drugs and vaccines. Commonly used animal models are mainly rodents, which make up a large part of reservoir hosts of leishmaniasis. Examples of standard rodent models are the laboratory mouse (Mus musculus) and the golden hamster (Mesocricetus auratus), however, higher models such as non-human primates or dogs are also being used. Animals that are relatively new to leishmaniasis research are wild rodents, which appear to be ideal experimental models for studying the natural dynamics of infections. Key words: animal models, laboratory animals, rodents, Leishmania, leishmaniasis
Intraspecific communication in rodents with a special focus on the model genus Rattus
Rychtecká, Eliška ; Rudolfová, Veronika (advisor) ; Vojtěchová, Iveta (referee)
The genus Rattus includes several dozen species. Among the most significant that I am focusing on in this work are the Norway rat (Rattus norvegicus), the black rat (Rattus rattus) and the Polynesian rat (Rattus exulans). Representatives of these species are social animals inhabiting different enviroments, whether they are tree canopies or burrow systems. Intraspecific communication of rodents is very diverse, specifically in the genus Rattus. According to the types of signals, intraspecific communication can be divided into acoustic, visual, tactile or chemical. We can distinguish multimodal communication as a special chapter, where signals from different modalities occur together, interwine or are gradually added to each other. Individual species of the genus Rattus can differ in the form of signals. Furthermore these signals also differ between individual sexes so we could set apart communication between males and females during mating. Key words: rodents, norway rat, black rat, communication, signal, vocalization, posture, marking
Functional and pathological changes in the stomach of hosts infected with gastric cryptosporidia
The aim of this study was to observe and record the effect of infection with gastric species of the genus Cryptosporidium on the gastric characteristics of their hosts. The species Cryptosporidium proliferans was used for a series of experimental infections, and three types of model hosts - BALB/c mice, C57Bl6 mice and multimammate mice (Mastomys coucha) - were used as experimental animals. Oocysts were detected in the faeces of infected animals by standard parasitological, specific staining and molecular methods and the course of infection and pathogenicity of the Cryptosporidium species were described. Groups of animals comprising of 1-3 animals were humanely euthanized at seven-day intervals up to 70 days after infection. C. proliferans was found to have a direct effect on pH change in selected host types, with an increase in pH at the peak of infection and, depending on the host type, either an increase until the end of the experiment or, in the case of self-healing, a gradual return to physiological values. Pathological changes of the gastric mucosa during the course of the infection were recorded by histological methods, which were its thickening and increased mucus production, as well as the presence of inflammatory infiltrates and the intensity of the infection, to varying degrees across the selected hosts and the course of the infection. We found that even with short-term infection in BALB/c and C57Bl6 mice, there is both mucosal enlargement and thickening, although the pathological changes in these types of mice are not as extensive as in multimammate mice, which do not self-heal.
Faktory ovlivňující excystaci žaludečních kryptosporidií hlodavců
The aim of this study was to determine the effect of host body temperature and en-vironmental pH on the excystation and preservation of the ability to infection of rodent gastric cryptosporidia oocysts. The infectivity of unexcysted oocysts was further examined. Immunodeficiency SCID mice (Mus musculus) were infected with C. proliferans oocysts, then their faeces were collected and individual experi-ments were performed. The effect of temperature on excystation, when oocysts were placed in water baths at the appropriate temperature (32-44 °C) and the effect of pH, when oocysts were exposed to solutions of different pH (2-7), was investi-gated. Cell separation was then performed using a flow cytometer and the values obtained were recorded in the tables. The most oocysts excysted at 40 °C and pH 7. An autopsy of infected mice was also performed to determine the infectivity of oo-cysts from various parts of the digestive system. All taken oocyst samples were infectious for the subsequent host. Infection experiments, which were further car-ried out revealed, that unexcysted oocysts exposed to hypochlorite and laboratory temperatures retain their ability to infect. In contrast, the oocyst sporozoites that excysted were susceptible to both hypochlorite and room temperature, thus losing the ability infect the subsequent host.
Hlodavci jako rezervoár hantavirů
This study reveals the presence of hantaviruses in free-living rodents and insectivores in urban areas in the Czech Republic. A large number of hantavirus reservoir hosts were tested for hantavirus RNA in different tissues, using universal and specific primers for amplification of the large and medium fragments of hantavirus genomic RNA. Phylogenetic relationships of obtained nucleotide sequences of hantaviruses were reconstructed. Four different species of hantaviruses were detected, including two species pathogenic (or potentially pathogenic) for humans, suggesting a threat for public health. Additionally, inter-family spillover infections and hantavirus species-associated tissue tropism were recorded in rodent hosts.
Laboratorní test disasortativního párování u hraboše polního - literární rešerše
BÍLKOVÁ, Pavlína
Petrásková P. (2019): Laboratorní test disasortativního párování u hraboše polního - literární rešerše [Laboratory test of disassortative pairing in the common vole - literature search. Bc. Thesis in Czech]-49 pp. , Faculty of Sciences, University of South Bohemia, České Budějovice, Czech Republic. The aim of this work is to use the literature research to map current knowledge about the effect of odour preference on reproductive success in mammals focusing on voles. As assortative pairing is referred to each form of non-random pairing. Most of the time is meant a situation in which individuals who have similar phenotypes pair more often. The opposite is the situation where individuals with different phenotypes pair more often. This is sometimes referred to as negative assortative or disassortative pairing. In particular, this study deals with non-random pairing among to body odour . These are mainly linked to genes for the major histocompatibility complex (MHC) in animals, which play a key role in the immune system. MHC gene products found in various body secretions form the specific odour of each individual. In the research part were searched question for following questions: How is the breeding partner chosen? Is Assortative or Disassortative Pairing More Frequent? What information does body odour convey? What channels is the odour information transmitted and received? How is odour preference testing solved in laboratory conditions? In the practical part, a plan of the experiment is presented in which T-labyrinth will play the main role in determining the odour preference. Under laboratory conditions, voles will have plenty of time to complete the process
Optimization of litter size in rodents
Cingelová, Alexandra ; Dušek, Adam (advisor) ; Sedláček, František (referee)
Optimization of litter size can be defined as adjustment of litter size according to actual environmental conditions or condition of mother to reach a compromise between the maximum number of offspring and their individual fitness. Rodents are an ideal taxon to study this topic because of their enormous interspecific variability in life strategies across the whole order. The variation in litter size among rodent species was influenced by countless ecological and social factors during their evolution. These include the geographical location of the breeding populations, various life and reproductive strategies such as r-/K-strategy, the presence of altricial or precocious offspring, various ways of life, the presence of water in the environment, predation rate, hibernation, and sociality. Litter size can be adjusted already before fertilization, for example by choosing a partner, by timing reproduction, condition, age and social status of the mother. Genetic factors affecting litter size are, for example, MHC glycoprotein polymorphism and t-haplotype. Reduction of the litter size may occur before insemination by influencing the ovulation rate, female reproductive hormone levels and exposure to the stressors, during implantation by selective abortion, and postpartum by infanticide, siblicide, and...
Adaptive radiation of the genus Rattus
Skalíková, Hana ; Frynta, Daniel (advisor) ; Mazoch, Vladimír (referee)
Rats are an important group of rodents originating and living mainly in southeast Asia. They are important pests and reservoirs of zoonosis. Yet, about many species we only have basic information. Here, I summarized available information about 66 species of the genus Rattus and 10 species of the genus Bandicota, Diplothrix, Limnomys, Nesokia and Tarsomys. I focused on distribution, ecology and morphology (body lenght, tail lenght, hind food lenght and ear lenght) and their mutual relationships. The body lenght differs beetwen phylogenetic lineages and beetwen habitats. The other morphological characters (tail lenght, hind food lenght and ear lenght) correlated with body lenght. Further, I describe an adaptive radiation of rats. Rats are separated into several lineages, diferring in their geographic distribution and ecology. Moreover, many species are commensal, that is benefiting from close relationship with humans. Commensalism species can be found in several lineages of rats, therefore commensalism probably developped independently more than once. The commencalism was origined several times. I discuse why are some commensal species more successful than others. Key words: adaptive radiation, Bandicota, commensal species, ecomorphology, Rattus, rodents, southeast Asia

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