National Repository of Grey Literature 34 records found  previous11 - 20nextend  jump to record: Search took 0.01 seconds. 
Faktory ovlivňující excystaci žaludečních kryptosporidií hlodavců
SCHULZOVÁ, Tereza
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.
\kur{Apodemus} vs. \kur{Eimeria}: Evolutionary factors of speciation and genomic diversification in host-parasite system
MÁCOVÁ, Anna
This thesis discusses and explains phylogenetic patterns observed in two different organisms: Eimeria, an unicellular parasite, and Apodemus, a rodent that often serves as a host for this parasitic species. The situation in rodents is intuitive, clearly reflecting their biogeographic history. Phylogenetic pattern in A. agrarius corresponds with its spread from the core locality of its distribution eastward. The lack of the genetic variability in European populations hints the recent origin of this population with the low number of founders. The phylogeny of A. flavicollis, a rodent inhabiting almost the whole Europe, reflects the situation during the last glacial maximum (i.e. speciation in several subpopulations that did not interbreed, but retained their independent nature). The situation in Eimeria is more complex. Parasites always fight in "arm races", trying to accommodate to their hosts as best they can, and to avoid their defense. This results in coevolutionary events such as cospeciation, host switches, duplications, and other events that form the genetic variability in parasites. The study of evolutionary relationships in Eimeria may be difficult due to lack or morphological and/or relevant molecular data. This thesis adds more information to this view. Several other studies were also included in this thesis to provide a broader picture of the complexity of host-parasite systems.
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
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
The detection of thermal windows in fossorial rodents with varied sociality degree
VEJMĚLKA, František
Eight rodent species with fossorial activity differing in a number of characteristics such as ecology, climatic conditions, geographical distribution, or kinship were studied using infrared thermography in order to describe their surface temperature and its patterns. An attempt to describe the relation between surface temperature and varied social organisation in burrowing rodents was made.
Využití pokusných zvířat v ČR
MRÁZKOVÁ, Lucie
The animal experiments seem to be current theme of these days. This thesis is focused on using animals, especially rodents, in the Czech Republic for the last ten years. There is also emphasis on the legal principles of animal protection and observance of three "R" principles. In this study there were used data from available sources about using laboratory animals in the Czech Republic. Also there was prepared a questionnaire research in different scientific institutions which use animal models in their researches. There were found out from available sources that the amount of experimental animals is on the same level (about 230 000) during the years 2006-2015. There were no deflection. Also this fact is the same for using rodents (about 120 000) as biomodels. Further there was found out that the laboratory mouse (Mus musculus var. alba) is the most used experimental model. 66,7% of questioned respondents considered the laboratory mouse the most common used laboratory animal and 60% of questioned respondents supposed that the number of used laboratoty animals was decreasing.
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...

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