National Repository of Grey Literature 5 records found  Search took 0.00 seconds. 
Význam vitaminu D a jeho metabolitů v reprodukci živočišných organismů
Červenka, Jiří
Vitamin D is considered to be a group of molecules that have many functions in animal organisms. The best known of these is the key role in calcium and phosphorus homeostasis and regulation of bone mineralization. In recent years, however, many new functions of this vitamin have been discovered, such as the regulation of cell proliferation and differentiation, its influence on the immune system or its function in animal reproduction. This thesis deals with the importance of vitamin D in animal reproduction with an emphasis on livestock. In the literature review, the occurrence of receptors for vitamin D in cells of various types of different tissues of reproductive system, particularly in mammals and birds, and the function of various metabolites mediated by these receptors are discussed in the individual chapters. The thesis includes the design of methodology, which would test the effect of vitamin D on reproduction of the male and female domestic chickens. The hypothesis could verify, whether or not, Rhode Island Red cockerels, that would be fed a diet with a higher vitamin D content would demonstrate better ejaculate parameters and higher fertilization of eggs laid by Rhoade Island White hens inseminated with this semen. Furthemore, a solution is proposed to verify the hypothesis, assuming higher hatchability and lower embryonic mortality in hens fed higher vitamin D feed mixture. The result would be compared with hens and roosters of the same breeds, reared in an environment with the same conditions, fed a vitamin D deficient feed mixture.
Parous and nulliparous female detection in blood-sucking nematocera insects
Mračková, Marie ; Votýpka, Jan (advisor) ; Král, David (referee)
Nematocerous insects belong to the order Diptera, one of the largest and worldwide spread groups of insects. Haematophagous species act not only as tormentors, but also as vectors of various pathogens. The first section of this thesis reviews about insetct's reproductive systems, multiple blood-feeding, autogeny and development of ova; the information which are necessary for the transmission understanding. The principal topic of the thesis is reviewing methods for distinguishing parous and nulliparous females, which are commonly used for four Nematoceran groups: mosquitoes (Culidicade), black flies (Simuliidae), sand flies (Phlebotominae) and biting midges (Ceratopogonidae, the genus Culicoides). The section is focused mainly on family Culicidae, because the methods used for mosquitoes were the groundwork for developing methods suitable for the other groups. Some of the procedures, for example counting folicular dilatations or assessing the condition of tracheoles in the ovaries, are used for most of the studied groups; others, like pigmentation of the abdominal wall in the genus Culicoides, can be used only for one group. Knowledge of the female parity is very important for epidemiological and ecological studies, because only parous females, previously blood-fed on infected hosts, can transmit...
Parous and nulliparous female detection in blood-sucking nematocera insects
Mračková, Marie ; Votýpka, Jan (advisor) ; Král, David (referee)
Nematocerous insects belong to the order Diptera, one of the largest and worldwide spread groups of insects. Haematophagous species act not only as tormentors, but also as vectors of various pathogens. The first section of this thesis reviews about insetct's reproductive systems, multiple blood-feeding, autogeny and development of ova; the information which are necessary for the transmission understanding. The principal topic of the thesis is reviewing methods for distinguishing parous and nulliparous females, which are commonly used for four Nematoceran groups: mosquitoes (Culidicade), black flies (Simuliidae), sand flies (Phlebotominae) and biting midges (Ceratopogonidae, the genus Culicoides). The section is focused mainly on family Culicidae, because the methods used for mosquitoes were the groundwork for developing methods suitable for the other groups. Some of the procedures, for example counting folicular dilatations or assessing the condition of tracheoles in the ovaries, are used for most of the studied groups; others, like pigmentation of the abdominal wall in the genus Culicoides, can be used only for one group. Knowledge of the female parity is very important for epidemiological and ecological studies, because only parous females, previously blood-fed on infected hosts, can transmit...
Sterilizační účinek oostatického pentapeptidu na reprodukci Pyrrhocoris apterus
Němec, Václav ; Tykva, Richard ; Hlaváček, Jan ; Holík, Josef
The effect of an oostatic pentapeptide, H-Tyr-Asp-Pro-Ala-Pro-OH, on reproduction of the bug Pyrrhocoris apterus was studied. The peptide decreased the number of laid eggs in the first ovarian cycle.
Binding sites for oostatic peptides in organs of fly .I.Neobellieria bullata./I..
Nazarov, Elšan ; Holík, Josef ; Tykva, Richard ; Hlaváček, Jan ; Bennettová, Blanka ; Slaninová, Jiřina
Using tritiated peptides Asp-Pro, Tyr-Asp-Pro-Ala, Tyr-Asp-Pro-Ala-Pro binding experiments with homogentates on membrane preparations of ovaries were performed. Very low degree of specific binding was detected.

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