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tom 67
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nr 03
EN
This paper summarizes the current state of knowledge regarding the influence of physical exercise on immunity mechanisms in horses. Results of many studies indicate that exercise has an immunomodulating effect on horses. The immunological reaction depended on the intensity of physical exercise. It was found that moderate (single or cyclical) physical exercise stimulated the immunological system (increased the number and activity of immunological cells), while exhausting physical exercise decreased the efficiency of the innate and adaptive mechanisms of immunity. Epidemiological data confirm that the intensive exercise can increase the incidence of respiratory tract infections in horses, whereas moderate exercise presumably decreases the hazard of infection. In order to minimize the exercise-induced risk of infection, regular vaccinations, monitored training, control and supplementation of diet, reducing the environmental stress and, if necessary, chemo- and immunotherapy were recommended.
EN
Honey bees (Apis mellifera) are constantly exposed to contact with many types of pathogens. However, during evolution they developed a number of immune mechanisms. At the individual level, they comprise 1) resistance mechanisms associated with anatomical and physiological barriers of the body, 2) cell-mediated immunity involving hemocytes (including plasmocytes, lamellocytes, and granulocytes), 3a) congenital humoral resistance related to the activity of lysozyme (N-acetylmuramylhydrolase), the prophenylooxidase system (ProPO) and hemagglutinins (lectins), and 3b) induced humoral resistence based on the action of antimicrobial peptides: apidicines, hymenoptecin, and defensins. In addition to the individual resistance of each bee, there is also a defense mechanism activated at the colony level. Shared secretion resistance is connected with the presence of antipathogenic compounds in secreta and in bee products. Social immunity is associated with hygienic and nursing behaviors, as well as with age polyethism in the colony, swarming (and the emergence of rebel workers), and the changing behavior of sick individuals. Many aspects and interactions between different types of resistance and immunity still remain unexplored. However, current research trends revolve around clarifying uncertainties so as to strengthen the natural resistance of bees and fight against pathogens that threaten the insects.
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Content available Wolne rodniki w inwazji pasozytniczej
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nr 1-2
17-22
EN
Highly reactive oxygen species potentially represent a powerful effector mechanism against parasites. They are produced during normal cellular metabolism, especially by activated phagocytes. As can be seen from many studies protozoan and helminth parasites appear to have one or more anti-oxidant enzymes able to scavenge or quench the reactive free-radicals, and there is strong evidence that such enzymes may play crucial role in protecting against host response. Presented there review illustrates that methods to block anti-oxidant protection of parasites may be new field in the search for improved ways to inhibit parasitic survival.
EN
In terms of its anatomy and functions, the reproductive system of birds is significantly different from the one found in mammals. It consists of only the left ovary and the left oviduct, which is constantly exposed to ascending infections because of its connection with the cloaca. Hence, the proper functioning of humoral and cell-mediated local immune mechanisms in this system is very important for maintaining its physiological functions. The expression of Toll-like receptors and the presence of T and B lymphocytes have been demonstrated in both the ovary and the oviduct of chickens. CD4⁺ T cell subpopulation is distributed mainly in the lamina propria of the oviduct, whereas in the submucous membrane and muscular layer these cells are found less frequently. CD8⁺ T lymphocytes are equally distributed in all abovementioned layers of the oviduct wall. IgY⁺ B cells are distributed among the epithelial cells, and they are closely connected with the glandular tissue of the oviduct, mainly in the infundibulum, magnum, and uterus regions. IgA⁺ and IgM⁺ B cells are present in the entire oviduct, but mainly in the glandular tissue of the magnum. IgY⁺ B cells have not been detected in the ovary, unlike IgM⁺ B cells, which have been demonstrated in the ovary stroma. In addition to T and B cells, antigen-presenting cells are present in the follicle wall and in the oviduct. During the early stages of reproductive maturation, a decrease in the number of immunocompetent cells is observed in the reproductive system, and the local immnosuppression increases the susceptibility of birds to Salmonella Enteritidis infections. The number of T and B lymphocytes in the mucous membrane of the oviduct decreases with age, which facilitates infections of the reproductive system. Additionally, the local immune mechanisms of the reproductive system in birds involve the transfer of protective IgY, IgA and IgM maternal antibodies to hatching eggs. The local immune mechanisms of the reproductive tract are responsible for preventing infections that disturb the physiological functions of the reproductive system and for protecting eggs from contamination.
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