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The studies on the reproductive system of P. fasciata were based on 43 specimens. Two main types of the reproductive system can be distinguished in the studied population. Two types of reproductive system were the most frequent (20.93% each): with symmetrical ejaculatory ducts without a loop and symmetrical seminal vesicles reaching the end of the first pair of testes, situated next to the testes (adult individuals) (fig. 23) and with symmetrical ejaculatory ducts without a loop (fig. 21) and symmetrical poorly developed seminal vesicles situated asymmetrically anterior to the first pair of testes (juvenile individuals). The structure of the reproductive system corresponding with the description of the type specimen (BRUMPT, 1900) was not observed in the studied population.
The authors describe an individual of the female Ascaris suum Goeze with a unique genital system. A female with such an anomaly was found during laboratory classes of Invertebrate Zoology at the Faculty of Biology and Environmental Protection, NCU. The specimen was about 200 mm long, and the total length of the reproductive system was 1970 mm. Further comparative analysis between unchanged and changed individuals revealed differences in the length of individual sections of the studied system, as well as in the diameter of the uterus. The described case is extremely interesting because of the phenomenon of eutely occurring in nematodes. The exact cause and mechanism of abnormalities described in Ascaris suum are not known and difficult to explain experimentally because of the extremely small number of these anomalies. Moreover, the interpretation of the anomaly is difficult because of the specific behavior and complex morphogenesis of this endoparasite.
The aim of this work was to study the influence of hypokinetic conditions on the ovary and corpus luteum of pregnant rats. The rats were kept in hypokinetic conditions for 5 days in the period between the 13th and 18th days of pregnancy. A three-dimensional reconstruction of the ovary and corpora lutea and also a stereological evaluation of the luteal cells and their nuclei were performed using serially cut material. Hypokinesia caused a decrease in the mean volume of the ovary and individual corpus luteum and in the total volume of corpora lutea per ovary in immobilised animals as compared to the control. Moreover, a decrease was observed in the mean number of luteal cells and an increase in the size of these cells, as well as in the mean volume fraction of their nuclei. These results indicate that immobilisation of pregnant rats for 5 days considerably influences the morphology of the corpus luteum and luteal cells.
Both, earlier investigations and complete formulas of pet food for dogs show that professionally prepared pet food is based in 30% on the material of the plant origin. Our own investigations prove that animal feeding stuffs of the plant origin are very often vectors of many undesirable substances (including micotoxins) that are unfavourable for carnivores. Zearalenone is a micotoxin, which frequently occurs among them. It was revealed in pet food in quantities from 5.0-299.5 μg/kg- It is a very dangerous xenobiotic because of its quick and easy absorption in the organism after per os application in monogastric animals. It is also a sterid and despite its plant origin it binds estrogen receptors in the reproductive tract and causes its hypo- and dysfunction. It is clearly visible in young, growing organisms and those during the menopause. In bitches, dysfunctions of the reproduction system, such as: endometritis-pyometra syndrome, prolonged oestrus, ovarian cysts and others are often found. It is supposed that specific for this species hormonal regulation of the reproduction processes based on the long progesterone and prolactin cycles, and on high sensibility to estrogens plays an important role in the etiopathogenesis of these dysfunctions. The application of hormones in bitches in therapeutic and biotechnical (contraception) purposes are the other factors, which should be taken into account in this aspect. There are some suggestions that therapeutic management, unfortunately connected with mistakes in the medical art, is often a cause of pathological condition in a reproductive organ in bitches. However, another reason of these disorders may be that bitches take zearalenone with the commercial pet food. The long-lasting intake of the feed with a low dose of this micotoxin may be the factor, which complicates hormonal regulation of the reproduction processes and is the cause of many disorders. Our own pilotage investigations showed that application of zearalenone at a dose of 200 μg/kg b. w. for 7 days leads to apoptotic-like changes in granule cells in the bitch reproductive system, atresia of follicular cells and oedema and hyperplasia of the oviductal and uterine cells. They could also indicate a follicular phase of the oestrus cycle in bitch. However, it did not take place.
Spontaneous infection of horses with Equine Arteritis Virus can occur either through the respiratory or the reproductive system. In case of infection through the reproductive system, the semen of the convalescent stallion is the source of virus and the infection takes place during natural mating or artificial insemination. The main purpose of serological and virological investigations thus is to detect stallions infected with Equine Arteritis Virus being virus shedders from semen. In this study, samples of sera collected from horses kept in natural conditions were examined. They were investigated with virus neutralisation test for anti Equine Arteritis Virus antibodies using various Equine Arteritis Virus strains as antigens. In sera of the horses examined, high anti Equine Arteritis Virus antibody titers from modified Bucyrus Equine Arteritis Virus strain, passage 166 in RK-13 cells and from Wroclaw Equine Arteritis Virus, passage 20 in RK-13 cell line were shown. Although there were considerable differences in the level of anti Equine Arteritis Virus antibodies for the antigens used, serum samples identified in the standard virus neutralisation test as free from anti Equine Arteritis Virus antibodies remained negative for all Equine Arteritis virus strains used in the experiment.
According to literature of the problem, the disturbances of reproductiveness of human in various parasitic infections are discussed. The mechanisms disturbing the proper functioning of the hosts's reproductive system are not sufficiently understood. They may remain in association not only with a direct or indirect effect of the parasite on the host's endocrinal glands and sexual organs, but also with the host's overall reaction to stress or toxic influences. Parasite's activity may lead to abortion or a significant decrease in fetal body weight. Embryo or fetus may be also damaged in an intrauterine infection.
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