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201.
Porcine circovirus type 2 (PCV2) infections cause important respiratory diseases in the pig industry and are associated with many bacterial, mycoplasmal, and viral complications. In this study, a heterologous PCV2 major capsid protein (MCP) was expressed in the Bordetella bronchiseptica aroA mutant strain (BBS-MCP) and used as a live vaccine vehicle. Mice and pigs were immunized with live BBS-MCP via the intranasal route. The antibodies against MCP were induced successfully in the serum as determined by ELISA. In the PCV2 challenge experiment, viral DNA was removed successfully from the lymph nodes of pigs vaccinated with live BBS-MCP. Overall, BBS-MCP is believed to be a good candidate for the development of a live-attenuated vaccine against PCV2 infections.  相似文献   
202.
A single nucleotide polymorphism in the equine herpesvirus 1 (EHV-1) DNA polymerase gene (ORF30 A2254 to G) has been associated with clinical signs of equine herpes myeloencephalopathy (EHM). The purpose of our study was to determine the odds ratio for this genetic marker and EHM using a panel of field isolates from North America collected over the past twenty-three years. EHV-1 isolates cultured at the Cornell University Animal Health Diagnostic Laboratory from 1984 to 2007 were retrieved along with their clinical histories. DNA was extracted from these EHV-1 cultures and allelic discrimination was performed using real-time PCR. The results were confirmed by sequencing of the target region in ORF30. PCR and sequencing were in 100% agreement and showed that 19 out of the 176 isolates had the ORF30 G2254 allele (11%), of which16 were EHM cases and 3 respiratory or abortion cases. The odds of having neurologic disease with the ORF30 G2254 genotype were computed as 162 times greater than those with the opposite allele ORF30 A2254 (95% confidence interval: 35–742). Despite this strong statistical significance, 24% (5/21) of horses with neurologic disease in our study population harbored the “non-neurologic” form of the allele (ORF30 A2254), suggesting that other factors may also contribute to the onset of EHM.  相似文献   
203.
An outbreak of fatal hemorrhagic pneumonia with 70~90% morbidity and 50% mortality occurred in an animal shelter in Yangju, Gyeonggi Province, Korea. Clinically, the affected dogs showed severe respiratory distress within 48 h after arriving in the shelter. The dead were found mainly with nasal bleeding and hematemesis. At necropsy, hemothorax and hemorrhagic pneumonia along with severe pulmonary consolidation was observed, though histopathological analysis showed mainly hemorrhagic bronchopneumonia. Lymphoid depletion was inconsistently seen in the spleen, tonsil and bronchial lymph node. Gram-positive colonies were shown in blood vessels or parenchyma of cerebrum, lung, liver, spleen, and kidney. Also, Streptococcus (S.) equi subsp. zooepidemicus was isolated from the various organs in which the bacterium was microscopically and histologically detected. In addition, approximately 0.9 Kb specific amplicon, antiphagocytic factor H binding protein, was amplified in the bacterial isolates. In this study, we reported an outbreak of canine hemorrhagic bronchopneumonia caused by S. equi subsp. zooepidemicus in an animal shelter in Yangju, Korea.  相似文献   
204.
Discovery of Helicobacter (H.) pylori has led to a fundamental change in our understanding of gastric diseases in humans. Previous studies have found various Helicobacter spp. in dogs and cats, and pets have been questioned as a zoonotic carrier. The present study surveyed the Helicobacter infections and investigated the presence of H. felis and H. pylori infections in domestic and feral cats in Korea. Sixty-four domestic cats and 101 feral cats were selected from an animal shelter. Saliva and feces were evaluated by Helicobacter genus-specific polymerase chain reaction (PCR). Genus-specific PCR positive samples were further evaluated for H. felis and H. pylori using specific primer pairs. Thirty-six of 64 (56.3%) samples from domestic cats and 92 of 101 (91.1%) samples from feral cats were PCR positive; the positive rate of feces samples was higher than that of saliva samples in both groups. H. felis and H. pylori species-specific PCR was uniformly negative. The prevalence of Helicobacter spp. in feral cats was approximately two-fold higher than that of domestic cats. The fecal-oral route may be more a common transmission route not only between cats but also in humans.  相似文献   
205.
Aspergillus spp. are opportunistic pathogens which cause pulmonary aspergillosis in animals and humans with compromised immune systems. Two Eurasian black vultures (Aegypius monachus Linnaeus) were found dead or clinically ill from carbofuran insecticide during the winter of 2004. Carbofuran was detected in the stomach contents by gas chromatograph-mass spectrometry. Gross lesions showed severe granulomatous pneumonia and serofibrinous pleuropneumonia in both birds, with most lesions restricted to the pulmonary system. Histological lesions included pyogranulomatous pneumonia and suppurative parabronchiolitis/pleuritis/air sacculitis with a number of septated fungal hyphae, suggesting severe pulmonary aspergillosis. Fungal isolates from each vulture were identified as Aspergillus fumigatus by both lactophenol cotton blue staining and genetic analysis. This is the first report of pulmonary aspergillosis caused by A. fumigatus in wild Eurasian black vultures and suggests that Aspergillus infection could be an important cause of death in these birds which migrate from Mongolia to Korea during the winter. The incidence of the disease may be related to impaired immunity caused directly or indirectly by carbofuran poisoning.  相似文献   
206.
Active serologic surveillance is necessary to control the spread of the avian influenza virus (AIV). In this study, we evaluated a commercially-available cELISA in terms of its ability to detect AIV antibodies in the sera of 3,358 animals from twelve species. cELISA detected antibodies against reference H1- through H15-subtype AIV strains without cross reactivity. Furthermore, the cELISA was able to detect antibodies produced following a challenge of the AIV H9N2 subtype in chickens, or following vaccination of the AIV H9 or H5 subtypes in chickens, ducks and geese. Next, we tested the sensitivity and specificity of the cELISA with sera from twelve different animal species, and compared these results with those obtained by the hemagglutination-inhibition (HI) test, the "gold standard" in AIV sera surveillance, a second commercially-available cELISA (IZS ELISA), or the agar gel precipitation (AGP) test. Compared with the HI test, the sensitivities and specificities of cELISA were 95% and 96% in chicken, 86% and 88% in duck, 97% and 100% in turkey, 100% and 87% in goose, and 91% and 97% in swine, respectively. The sensitivities and specificities of the cELISA in this study were higher than those of IZS ELISA for the duck, turkey, goose, and grey partridge sera samples. The results of AGP test against duck and turkey sera also showed significant correlation with the results of cELISA (R-value >0.9). In terms of flock sensitivity, the cELISA correlated better with the HI test than with commercially-available indirect ELISAs, with 100% flock sensitivity.  相似文献   
207.
The effects of feeding chemically treated dietary supplements (CTDS) containing sunflower oil and dl-alpha-tocopheryl acetate (TA) on alpha-tocopherol content and fatty acid profile in edible tissues of lambs were estimated. Compared with lambs fed control diet (CD), lambs fed CD plus 250 IU of either TA or CTDS increased serum alpha-tocopherol. The CTDS-fed lambs further increased serum alpha-tocopherol by 29% over those fed CD plus 250 IU of TA. Lambs supplemented with TA or CTDS increased alpha-tocopherol in muscle and adipose tissues as compared with lambs fed CD. The CTDS-fed lambs had higher levels of alpha-tocopherol in gluteus medius (7.55 vs 6.05 mug/g), psoas major (7.43 vs 6.02 mug/g), and subcutaneous fat (12.6 vs 9.98 mug/g) compared with the TA-fed lambs. Feeding lambs CTDS also substantially increased levels of linoleic acid in the adipose tissues while decreasing the content of palmitic and oleic acids.  相似文献   
208.
In this study, micro-porous carboxymethyl cellulose (CMC) nonwovens were prepared by carboxymethylation of cellulose nonwovens produced by a wet-laid process and their properties were investigated for potential applications as adhesion prevention barriers. After carboxymethylation, the thickness and mean pore size of the cellulose nonwovens were increased, whereas their pore size distribution became narrower. Tensile strength of cellulose nonwovens was proportional to basis weight, and dramatically increased after carboxymethylation. CMC nonwovens immediately absorbed a phosphate buffered saline solution and showed swollen phase within 1 min. It was found that the thickness and pore size distribution of CMC nonwovens could be easily controlled by the wet-laid process. It is expected that the CMC nonwovens can be used as adhesion prevention barriers.  相似文献   
209.
Carbon nanotube (CNT)/magnetite (Fe3O4) nanocomposites were successfully fabricated by nanocoating. When the CNT/Fe3O4 nanocomposites were added to a carbonyl (CI) based magnetorheological fluid (MRF), the magnetic rheological properties of the MRF were enhanced. Such enhancement in magnetic rheological properties of the CI-CNT/Fe3O4 MRF is considered to be attributable to both the superparamagnetic property of the magnetic layer covering the CNT surface and the high length to diameter ratio of the CNT/Fe3O4 nanocomposite. Impact properties for CI-CNT/Fe3O4 MRF treated Kevlar fabrics were also tested, and improved impact properties were observed with external magnetic fields compared to CI-MRF treated Kevlar fabrics.  相似文献   
210.
A grid-based, KIneMatic wave STOrm Runoff Model (KIMSTORM) is described. The model adopts the single flow-path algorithm and routes the water balance during the storm period. Manning’s roughness coefficient adjustment function of the paddy cell was applied to simulate the flood mitigation effect of the paddy fields for the grid-based, distributed rainfall-runoff modeling. The model was tested in 2296 km2 dam watershed in South Korea using six typhoon storm events occurring between 2000 and 2007 with 500 m spatial resolution, and the results were tested through the automatic model evaluation functions in the model. The average values of the Nash–Sutcliffe model efficiency (ME), the volume conservation index (VCI), the relative error of peak runoff rate (EQp), and the absolute error of peak runoff (ETp) were 0.974, 1.016, 0.019, and 0.45 h for calibrated storm events and 0.975, 0.951, 0.029, and 0.50 h for verified storm events, respectively. In the simulation of the flood mitigation effect of the paddy fields, the average values of the percentage changes for peak runoff, total runoff volume, and time to peak runoff were only −1.95, −0.93, and 0.19%, respectively.  相似文献   
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