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991.
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The aim of the study was to investigate the influence of administration of probiotic bacteria on morphology of the gastrointestinal tract, liver and pancreas. The experiment was performed on 15 piglets at the age from 3 to 35 days, intragastrically administered with Bifidobacterium breve, B. animalis, and Lactobacillus acidophilus bacteria. In all piglets examined, the development of the gastrointestinal tract, liver and pancreas was observed to progress normally. After microflora administration to the piglets, an increase in the number of fibrocytes and fibroblasts was observed in the mucosa lamina propria of stomach and intestines. An increase was also reported in the number and activation of endocrine cells in the stomach and small intestines. The activity of alkaline and acid phosphatases, as well as succinic (SDH) and lactic (LDH) dehydrogenases, was found to be higher after the administration of probiotics. The administration of bacteria, especially of Lactobacillus acidophilus, caused an increase in the number of lymphocytes and lymphoid cells in lamina propria and intraepithelial lymphocytes in the small intestine. Enhanced proliferation of crypt cells was observed in the crypts of intestinal glands; however, there were no statistically significant differences in the PCNA index between the control and probiotic-administered groups. The performed study showed that the administration of probiotic bacteria has no negative impact on the morphology of the gastrointestinal tract, liver and pancreas and is found beneficial to its functioning and immune processes. 相似文献
993.
With the aim of developing therapeutic agents for strongyloidosis, the disease caused by infection with Strongyloides stercoralis, we established a novel assay technique using S. ratti and S. venezuelensis as models for S. stercoralis. The newly developed assay technique was found to more accurately represent treatment-induced larval paralysis than existing assays. Our method uses paper disks impregnated with the test solution, which even allows materials that are sparingly soluble in water to be tested. An inverted microscope was used to observe the larval states, and these states were recorded using a digital camera. We observed the activities of ivermectin and thiabendazole against larvae and calculated larval motility and velocity. These two factors were then combined to determine the overall viability of larvae at selected concentrations. The activities of the anthelmintics were compared by calculating the concentrations at which 50% viability was demonstrated, or in other words, the concentration at which paralysis was caused in 50% of the individuals (50% paralysis concentration; PC(50)). Evaluations after 24h of exposure yielded the following reproducible PC(50) values for ivermectin and thiabendazole, respectively: S. ratti, 2.4 and 140 microM; and S. venezuelensis, 2.3 and 190 microM. After treatment with ivermectin, there was a tendency for larval motility to be greater than that of the controls at low concentrations, a result that might be associated with its mechanism of action. 相似文献
994.
Gabriël S Geldhof P Phiri IK Cornillie P Goddeeris BM Vercruysse J 《Veterinary immunology and immunopathology》2005,104(3-4):265-272
Although the epitheliochorial placenta of ruminants does not allow passage of immunoglobulins from dam to foetus specific antibodies have been detected at birth in calves born to Schistosoma mattheei-infected cows. The present study determined the prevalence of calves born with specific antibodies for S. mattheei and the origin of these antibodies. For the determination of the prevalence, 100 calves born to infected mothers in an endemic area (Zambia) were examined, 24 were seropositive. To study the origin of these antibodies placentomes of 40 naturally S. mattheei-infected cows were examined for the presence of schistosome eggs and lesions which could explain foetal priming and/or leakage of maternal antibodies and/or antigen into the foetus. Tissue damage and schistosome eggs were observed on the maternal as well as the foetal side of the placentomes. In order to determine the specific nature of the antibody response, antibody profiles against soluble adult worm antigen preparation (SWAP) of S. mattheei were compared by Western blot between dams and their newborn calves (n = 8). The specific recognition profiles were identical for the seropositive calves and their dams on SWAP mattheei. Identical recognition profiles between dams and calves were also observed when sera were analysed on Escherichia coli, a pathogen of which the foetus should be free, and would indicate passive antibody transfer from the dam. In conclusion, the present study shows that S. mattheei could induce placentome lesions and that eggs can cross the placenta. Consequently, foeti can come into contact with S. mattheei antigens in utero, and might also contain maternal antibodies from leakage through placentome lesions. As such, the infection status of the mother could have far reaching effects on the immunological status of her offspring and modify their reaction upon infection. 相似文献
995.
The 1998 Report of the American Association of Feline Practitioners and Academy of Feline Medicine Advisory Panel on Feline Vaccines was developed to help veterinary practitioners formulate vaccination protocols for cats. The current panel report updates information, addresses questions, and speaks to concerns raised by the 1998 report. In addition it reviews vaccine licensing, labeling, and liability issues and suggests ways to successfully incorporate vaccination protocol changes into a private practice setting. 相似文献
996.
Yamashita K Tsubakishita S Futaok S Ueda I Hamaguchi H Seno T Katoh S Izumisawa Y Kotani T Muir WW 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(10):1025-1032
The cardiovascular effects of medetomidine, detomidine, and xylazine in horses were studied. Fifteen horses, whose right carotid arteries had previously been surgically raised to a subcutaneous position during general anesthesia were used. Five horses each were given the following 8 treatments: an intravenous injection of 4 doses of medetomidine (3, 5, 7.5, and 10 microg/kg), 3 doses of detomidine (10, 20, and 40 microg/kg), and one dose of xylazine (1 mg/kg). Heart rate decreased, but not statistically significant. Atrio-ventricular block was observed following all treatments and prolonged with detomidine. Cardiac index (CI) and stroke volume (SV) were decreased with all treatments. The CI decreased to about 50% of baseline values for 5 min after 7.5 and 10 microg/kg medetomidine and 1 mg/kg xylazine, for 20 min after 20 microg/kg detomidine, and for 50 min after 40 microg/kg detomidine. All treatments produced an initial hypertension within 2 min of drug administration followed by a significant decrease in arterial blood pressure (ABP) in horses administered 3 to 7.5 microg/kg medetomidine and 1 mg/kg xylazine. Hypertension was significantly prolonged in 20 and 40 microg/kg detomidine. The hypotensive phase was not observed in 10 microg/kg medetomidine or detomidine. The changes in ABP were associated with an increase in peripheral vascular resistance. Respiratory rate was decreased for 40 to 120 min in 5, 7.5, and 10 microg/kg medetomidine and detomidine. The partial pressure of arterial oxygen decreased significantly in 10 microg/kg medetomidine and detomidine, while the partial pressure of arterial carbon dioxide did not change significantly. Medetomidine induced dose-dependent cardiovascular depression similar to detomidine. The cardiovascular effects of medetomidine and xylazine were not as prolonged as that of detomidine. KEY WORDS: cardiovascular effect, detomidine, equine, medetomidine, xylazine. 相似文献
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