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Uterine inflammatory conditions with associated fertility disorders are still a serious problem in dairy cow breeding, causing significant economic losses for breeders. Losses result from the costs of uterine infection treatment, fertility disorders, low pregnancy rates, reduced production of milk and the culling of the best cows in the herd due to infertility. According to literature data, uterine inflammatory conditions in cows are closely connected with the postpartum period, and reproductive system infections that occur at this time may persist beyond the postpartum period and cause reduced fertility in cows. Pathogenic microbiota are an underlying cause of the development and persistence of uterine inflammatory conditions. The microorganisms with an affinity for the endometrium that are most frequently isolated from the uterus of cows with metritis and endometritis are Trueperella pyogenes, Escherichia coli, Fusobacterium necrophorum and Prevotella melaninogenicus. No infectious agents may be detected in some inflammatory conditions that are related to the disregulation of intracellular prostaglandin synthesis in uterine endometrial cells. This condition, which is due to infection, may persist for differing periods of time after the elimination of pathogens and may impair the fertility of cows. It is currently believed that the persistence of inflammatory conditions of the uterus depends on the level of anti-infective immunological mechanisms, which not only eliminate pathogens and damaged tissue, but also protect the endometrium thanks to their regulatory properties. Not all defence mechanisms in the uterus have been discovered. Phagocytosis is the first and most important mechanism of defence against pathogens in the uterus of cows, involving specialized phagocytic cells, mainly neutrophils, monocytes and macrophages, which belong to the innate immune mechanisms, as well as migrate from blood at the inflammation site as a specific response. Immune system cells and endometrial epithelial cells, which until recently have been believed to be only a passive barrier to microorganisms, are actively involved in the recognition and initiation of the antiinfective immune response. According to many authors, disorders of the local mechanisms of uterine immunity are a basic cause of metritis and endometritis in dairy cows.
The diagnosis of inflammatory conditions in the uterus depends primarily on the severity of the inflammation process and associated clinical symptoms. Because of the period of occurrence and characteristic signs, severe lesions in the uterus, such as metritis puerperalis, are not difficult to diagnose and do not require the use of diagnostic methods other than clinical examinations and, if necessary, additional tests to determine the general condition of the animals. However, in this case, it is important to precisely identify the pathogenic factor and to determine its susceptibility to antibiotics in order to define further treatment. Endometritis is the biggest diagnostic problem, especially its subclinical form, which can be diagnosed only by additional cytological or histopathological tests. These tests, although available, are not routinely performed in Poland at this time. The latest diagnostic methods, such as immunohistochemical tests or flow cytometry, have provided many previously unknown data, for example, on the action of the local resistance mechanisms in the uterus. Since the immune system of the uterus is not fully known, the above tests may improve the understanding of its activity or may help modulate its functions in the future as a potential preventative measure or treatment for inflammatory conditions of the uterus. The treatment of inflammatory conditions in dairy cows is currently based on two basic methods: intrauterine administration of antibiotics and intramuscular injections of prostaglandin-based preparations. The main goal of the treatment is to improve the fertility of cows in the herd, and since these methods are often ineffective, there have been attempts to treat endometritis with iodine-based preparations and preparations containing enzymes (trypsin, chymotrypsin and papain). They did not, however, improve the fertility of cows. The administration of non-steroid anti-inflammatory drugs to eliminate the inflammatory condition of the uterus and to prevent early deaths of embryos at the time of the greatest risk of embryo loss did not increase the number of pregnancies in cows either. Literature data suggest that immunomodulation and the use of probiotics may be useful in the prevention and treatment of endometritis.
The present study was undertaken to examine the effects of immunostimulation with isoprinozine (Isoprivet) on the hygienic quality of milk and the health status of mammary glands. Eight HF cows with mastitis whose milk did not meet the extra- class requirements were involved. The following examinations were performed: clinical examination of the udder, macroscopic assessment of milk secretions, FCR, milk cultures, quantitative determination of microorganisms and somatic cell count. No other preparations were used during the experiment. The preliminary results show that isoprinozine has beneficial therapeutic and prophylactic effects on dairy cows already affected or at risk of mastitis. Moreover, it markedly improves the parameters of hygienic assess- ment of raw milk whose quality is maintained within acceptable standards. The findings suggest that isoprinozine may be used as a stimulator of non-specific mechanisms of immune response during lactation in cows.
The aim of the study was to assess the effects of tamoxifen and cyclophosphamide on the selected cell-mediated immunity parameters in dogs. The study included 18 dogs aged 5-10 years. The experimental group consisted of 12 animals with neoplastic lesions classified as the first or second staging group (according to the WHO TMN classification). This group was divided into two subgroups: I - six dogs receiving oral tamoxifen, and II - six dogs with cyclophosphamide administered orally. The control group included six healthy dogs. The blood was sampled from the saphenous access vein two times at 14-d intervals before the drug administration, three times every 7 d during administration, and two times every 14 d after completion of the therapy. The basic blood tests were carried out and the subpopulations of TCD4+ and TCD8+ lymphocytes, and phagocytic activity of granulocytes and monocytes were determined using flow cytometry. It was found that tamoxifen induced a marked increase in WBC and neutrophil counts, increased phagocytic activity of monocytes, and changed the CD4+:CD8+ ratio (in favour of cytotoxic lymphocyte subpopulation). These findings indicated the stimulation of cell-mediated immunity mechanisms. Cyclophosphamide caused a substantial decrease in the overall leukocyte pool and reduced the percentage of cells activated for phagocytosis, both neutrophils and monocytes even after completion of its administration, which proves its immunosuppressive effects.
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