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1.
Effect of bleaching on lipid content and composition of Okinawan corals   总被引:5,自引:0,他引:5  
Lipid contents and compositions of the bleached Okinawan corals were analyzed for the first time. Bleached corals collected at Sesoko Okinawa, Japan (26°38′N, 127°52′E), after the 1998 bleaching event showed decreased lipid content with a concomitant decline of wax in the lipid composition. The reductionin the lipid content of corals showed diversity depending on their colony morphology. On the whole, corals of massive morphology were relatively rich in lipid even after the bleaching event, and hence lesser reduction in the lipid content compared with the cases for those of branching morphology. Furthermore, there was a positive correlation between lipid content and zooxanthellae density in the bleached corals, suggesting again the importance of symbiont for the supply of lipid to the host cells, and hence for the survival of the bleaching event.  相似文献   
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The present study was planned to evaluate a role of nitric oxide (NO) in the regulation of regular ruminal contractions in conscious sheep. Intravenous infusion of S-nitroso-acetyl-DL-penicillamine (SNAP) at doses of 3-30 nmol kg(-1) min(-1)for 30 minutes inhibited both the amplitude and frequency of ruminal contractions in a dose-dependent manner. However, intravenous infusion of Nomega-nitro-L-arginine-methyl ester (L-NAME) at doses of 0.3-3.0 micromol kg(-1) min(-1)did not alter the basal tone of intraruminal pressure and the amplitude of ruminal contractions. The frequency of contractions was slightly inhibited by L-NAME infusion at 1.0 micromol kg(-1)min(-1). The effects of L-NAME were abolished by simultaneous infusion of L -arginine at 30 micromol kg(-1) min(-1). These results suggest that exogenous NO can diminish the ruminal contractions, while endogenous NO is not involved in the regulatory mechanism of basal tone and regular phasic contractions of the rumen in healthy sheep.  相似文献   
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A latex agglutination test was evaluated as a method for the detection and titration of antibodies against swine Haemophilus infection and it was found that the test is applicable to the etiologic diagnosis of Haemophilus infection in swine. In swine infected experimentally with H. pleuropneumoniae (H. parahaemolyticus), the micromethod of agglutination using latex particles coated with antigens of H. pleuropneumoniae was found to be comparable agar-gel immunodiffusion and complement-fixation tests, which have previously been used for the etiologic diagnosis of the disease. Antibody titers determined by the latex agglutination test corrlated well with those determined by the other serological tests. The latex agglutination test tended to detect antibodies earlier than any of the other tests. By the latex agglutination test, weak cross-reactions were observed among different serotypes of H. pleuropneumoniae, whereas no cross-reaction was demonstrated between H, pleurophneumoniae and H. parasuis. The latex agglutination test was found to be simple and useful for the serological survey of swine Haemophilus infection, especially when dealing with a large number of samples.  相似文献   
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A cDNA library was constructed with Eimeria necatrix merozoite mRNA and immunologically screened by chicken sera against this parasite. One of the positive clones containing an insert of 879 nucleotides, pNP19, showed similarity to part of a published gene expressed in E. tenella merozoite by the homology search system. The inserted DNA was subcloned into baculovirus, and a 35-kD protein was expressed, purified, and used for the antigen in enzyme-linked immunosorbent assay (ELISA). Antibodies from the chickens vaccinated with the E. necatrix attenuated strain, Nn-P125, were detected from 14 days after vaccination by ELISA. The mean absorbance increased rapidly to a peak around 21 days after vaccination; thereafter, it began to decline. Even though some of the vaccinated chickens showed very low levels of antibody response to the recombinant protein 56 days after vaccination, they were protected against challenge with virulent strain of E. necatrix. The mean absorbances in sera from both vaccinated and nonvaccinated chickens highly increased 14 days after challenge. On the other hand, the antibody was not detected in ELISA when chickens were exposed to other Eimeria species such as E. tenella, E. acervulina, and E. maxima. These results demonstrate that this recombinant protein is suitable for detecting the specific antibody in chickens infected with both attenuated and virulent strains of E. necatrix.  相似文献   
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Plasma secretin and cholecystokinin (CCK) levels and the periodic secretions of the exocrine pancreas were studied simultaneously with the duodenal migrating myoelectric complexes (mmc) in six milk-fed calves which had been starved overnight. The experiments were performed first when the calves were 10 to 16 days old and subsequently when they were 36 to 45 days old. Plasma secretin and the secretion of pancreatic juice fluctuated periodically in phase with the duodenal MMC: plasma secretin, and the pancreatic secretion of water and protein were significantly higher during the phase of irregular spiking activity than during the phase of no spiking activity in both investigations. Plasma CCK did not change throughout the MMC. The intravenous infusion of secretin at 120 pmol kg−1 bodyweight for one hour markedly stimulated pancreatic secretion and prolonged the duodenal MMC cycle, but it did not abolish pancreatic and duodenal periodic activity.  相似文献   
9.
Nine thousand commercial breeder chicks (Chankee) reared in a floor pen were exposed to restricted numbers of Eimeria tenella and E. necatrix oocysts to confer immunity. Antibody induction in these chicks was examined by the enzyme-linked immunosorbent assay (ELISA) with antigen prepared from E. tenella oocysts. The oocyst excretion pattern demonstrated recycled infections which continued in these chicks for greater than or equal to 22 days after exposure. Antibody levels in their sera, as determined by the mean absorbence values in ELISA, increased gradually up to 38 days post-inoculation. Mean absorbence values of sera from control chicks remained at a low level. When infected and control chicks were challenged with the two species of coccidia, the test chicks were protected against both species. The antibody level did not change for 8 days in the challenge groups, while in the control chicks, absorbence in ELISA rose significantly and the mean absorbence value was higher than that in immunized chicks. Some factors which influence the results of ELISA are considered and the applicability of this method to measuring immunity against coccidiosis in chickens is discussed.  相似文献   
10.
Eimeria necatrix-specific ELISA, using a recombinant antigen (the cDNA-clone NP19 expressing protein), was utilized to detect antibodies against E. necatrix in breeder pullet flocks that had previously received an attenuated live vaccine to E. necatrix. Vaccinated flocks were discriminated significantly from non-vaccinated flocks by their antibody titers and antibody positive rates at 30-55 days post-vaccination. In addition, E. necatrix-oocysts were confirmed in fecal samples of vaccinated flocks using PCR in the case where the antibody positive rates rose. These findings implied that the vaccination prompted repeated infections, and consequently the chickens generated antibodies and secured their protection against virulent field-E. necatrix. Therefore, the ELISA was suggested to be a useful tool to estimate the immune state of chickens as a result of vaccination with a live E. necatrix-vaccine.  相似文献   
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