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31.
Llewellyn ZN Ou X Chang GJ Schmitt B Salman MD Akkina RK 《American journal of veterinary research》2000,61(11):1358-1363
OBJECTIVE: To compare molecular associations between the vesicular stomatitis virus (VSV)-New Jersey isolates of the 1995 outbreak with those from previous outbreaks between 1982 and 1985 in the western United States. SAMPLE POPULATION: 23 virus isolates considered representative of the 1995 outbreak of vesicular stomatitis. PROCEDURE: Viral gene coding for surface-envelope protein G was evaluated by use of nucleotide sequencing and phylogenetic analysis. RESULTS: Changes in up to 0.77% of the nucleotide bases and 1.35% of the amino acids were detected among the 1995 viral isolates, whereas changes in up to 3.2 and 2.9% of the nucleotides and amino acids, respectively, were found, compared with the 1982 to 1985 viruses. Insertions or deletions were not found in the entire gene, which spanned 1,554 nucleotide bases. CONCLUSIONS AND CLINICAL RELEVANCE: Phylogenetic analysis indicated that the 1995 VSV-New Jersey belongs to a lineage distinct from that of the 1982 to 1985 viruses that caused previous outbreaks in the western United States. Furthermore, it also is distinct from strains from Central America and from the Georgian Hazelhurst strain. 相似文献
32.
Dong Ruan Qiuli Fan Ahmed Mohamed Fouad Yunyun Sun Shengshu Huang Aiji Wu Chuxiao Lin Zhixiang Kuang Chang Zhang Shouqun Jiang 《Journal of animal science》2021,99(2)
Essential oils are plant-derived aromatic volatile oils, and they contain bioactive compounds that have been shown to improve poultry nutrition. In this study, we investigated the effects of oregano essential oil (OEO) on intestinal antioxidative capacity, immunity, and gut microbiota of young yellow-feathered chickens. A total of nine hundred and sixty 1-d-old female Qingyuan partridge chickens were randomly allocated to four treatment groups with six replicates of 40 birds each, and the feeding trial was lasted for 30 d. The controls were fed on a basal diet without in-feed antibiotics; the birds in the antibiotic group were fed the basal diet supplemented with 20 mg/kg virginiamycin; the remaining birds were fed the basal diet containing 150 or 300 mg/kg OEO, respectively. Dietary supplementation with 150 or 300 mg/kg OEO increased average daily feed intake (P = 0.057) and average daily gain (P < 0.05). The activities of glutathione peroxidase and total antioxidative capacity in plasma, jejuna, and ileal mucosa were increased by OEO supplementation (P < 0.05), with a trend of lower jejunal content of malonaldehyde (P = 0.062). Moreover, dietary OEO increased the content of secretory immunoglobulin A (P = 0.078) and the relative expression of Claudin 1, Mucin 2, and Avain beta-defensin 1 in ileum (P < 0.05). Sequencing data of 16S rRNA indicated that dietary OEO increased the relative abundance of Firmicutes phylum, and Clostridium and Lactobacillus genera, and decreasing that of Romboutsia. Functional analyses indicated that microbial amino sugar and nucleotide sugar metabolism, replication, and repair systems were higher in OEO groups than those of controls and antibiotic treatment. In conclusion, dietary supplementation with OEO enhanced growth performance, alleviated local oxidative stress in intestine, improved production of natural antibodies, and favorably modulated intestinal microbiota composition. 相似文献
33.
The objective of this study was to develop equations for estimating ileal digestible crude protein (CP) and metabolizable energy (ME) contents of meat meal (MM) and meat and bone meal (MBM) as feed ingredients for pigs based on in vitro assays. Test ingredients were 4 sources of MM and 3 sources of MBM. Ash and CP contents of the ingredients ranged from 3.8% to 33.1% and 46.8% to 82.9% (as-is basis), respectively. In vitro ileal disappearance (IVID) of CP was determined and ileal digestible CP content was calculated by multiplying CP content by IVID of CP. In vitro total tract disappearance (IVTTD) of dry matter (DM) was determined and ME was calculated using gross energy, CP contents, and IVTTD of DM. The IVID of CP and IVTTD of DM ranged from 77.2% to 88.7% and from 82.7% to 92.4%, respectively. Calculated ileal digestible CP and ME contents ranged from 37.8% to 73.5% DM and 2,405 to 3,905 kcal/kg DM, respectively. Ash contents were negatively correlated (P < 0.001) with CP (r = −0.99), in vitro ileal digestible CP (r = −0.97), gross energy (r = −1.00), in vitro digestible energy (r = −0.97), and adjusted ME (r = −0.97). The most fitting equations for ileal digestible CP and adjusted ME were: ileal digestible CP (% DM) = 11.91 − 0.90 × Ash (% DM) + 0.74 × IVID of CP (%) (R2 = 0.99) and adjusted ME (kcal/kg DM) = 130.85 − 50.90 × ash (% DM) + 47.06 × IVTTD of DM (%) (R2 = 0.99). To validate the accuracy of the prediction equations for ME, mean bias and linear bias were determined using a regression analysis. Calculated ME values of MM and MBM were in a good agreement with data obtained from animal experiments based on a statistically insignificant bias in the models. In conclusion, ME concentrations of MM and MBM as swine feed ingredients can be calculated using ash concentration and in vitro disappearance of dry matter. 相似文献
34.
Immunogenicity and haemagglutination of recombinant Avibacterium paragallinarum HagA 总被引:1,自引:0,他引:1
Inactivated vaccines of Avibacterium paragallinarum provide protection and reduce the economic losses caused by infectious coryza. However, inactivated bacterins provide protection only against the Page serovars included in the vaccine. In this study, we investigated the immunological properties of a functional recombinant haemagglutinin protein (rHagA) derived from a Taiwan isolate strain A9 as the immunogen for vaccination. The rHagA subunit vaccine protected 71% of immunized chickens against 10(10) colony-forming units (CFU) of viable A9. Vaccinated chickens which showed no clinical signs of coryza developed haemagglutination inhibition (HI) titers of 1:10 or greater. Haemagglutination (HA) of serovars A and C was not affected by the presence of rHagA specific antiserum. The HA of rHagA could only be induced against formaldehyde-fixed chicken red blood cells (FA-RBCs). These results suggested that HagA is a moderate immunogen and might not be a major haemagglutinin in vivo. However, HagA might be involved in haemagglutination when treated serovar C aggregates fixed RBCs in vitro. 相似文献
35.
以7个菜豆品种为试材,采用对冷害指数以及相对电解质渗透率进行测定的方式,筛选出耐低温型菜豆品种和低温敏感型菜豆品种,并对其低温驯化过程中内源多胺含量进行测定,研究了腐胺、亚精胺和精胺在响应低温驯化过程中含量的变化,以及对多胺合成分解酶基因表达量的影响,以期为今后菜豆外施多胺缓解低温胁迫提供参考依据.结果 表明:在低温驯化过程中2个品种叶片中腐胺和亚精胺的含量有明显增加,而精胺含量变化规律不明显.在低温驯化过程多胺合成酶基因ADC表达量上升,ODC表达量变化不明显,SAMDC表达量升高,SPDS和SPMS在2个品种中表现不一致;多胺分解酶基因DAO和PAO表达量上升,SMO在2个品种中表现不一致.综上所述,腐胺和亚精胺在植物体内的积累可能与提高菜豆苗期耐低温性有较大关系,并且它们的积累可能与ADC、SAMDS、DAO和PAO的表达水平有关. 相似文献
36.
为分析发酵乳对肥胖小鼠肝脂代谢和肠道菌群的影响,本研究将60只C57BL/6小鼠随机分为5组:正常对照组(CON)、模型组(MD)、易善复组(YG)、低浓度发酵乳干预组(LFG)和高浓度发酵乳干预组(HFG)。肥胖模型造模成功后进行为期6周的灌胃,试验结束测量小鼠的空腹体重和身长,计算LEE’S指数,采血检测生化指标,采集肝脏组织观察病理变化;采集小鼠盲肠内容物进行肠道菌群测序。结果表明:1)与CON相比,MD小鼠体重、LEE’S指数、ALT和AST均极显著提升(P<0.01),表明肥胖模型建立成功。2)与MD相比,发酵乳干预组小鼠体重、LEE’S指数、ALT和TC均极显著下降(P<0.01),其中AST和TG显著下降(P<0.05),同时发酵乳和易善复组小鼠肝组织脂肪变性有明显好转,基本没有明显的脂肪空泡。表明发酵乳可以抑制肥胖小鼠体重的增加,改善肥胖小鼠的肝脂代谢功能。3)与MD相比干预组小鼠肠道菌群的多样性水平有一定程度的恢复,尤其是厚壁菌门和拟杆菌门。表明发酵乳对于小鼠肠道菌群多样性的恢复有一定的作用。综上,本研究阐明了发酵乳对肥胖小鼠肝脂代谢和肠道菌群的影响,为功能型发酵乳的开发提供理论依据。 相似文献
37.
For centuries, red mold rice has been made by fermentation of cooked rice with Monascus species. However, the influence of different carbon sources on the metabolism of Monascus cells remains unclear. We compared the proteome response of Monascus pilosus to replacement of the rice starch fraction with lactose during cultivation, using two-dimensional gel electrophoresis, matrix-assisted laser desorption-ionization time-of-flight/time-of-flight mass spectrometry, and tandem mass spectrometry to identify the proteins expressed. The results showed that cell growth and monascorubramine pigment formation of M. pilosus were sensitive to rice starch limitation during cultivation. A total of 12 proteins were identified with statistically altered expression in the cells cultivated with lactose. These deregulated proteins were involved in glycolysis, TCA cycle, energy generation, protein folding, and peptide biosynthesis. The possible metabolic flux shifts induced by rice starch limitation were discussed. The results suggested that the suppression of monascorubramine formation could be related to the necessary energy-requiring adaptations executed in response to carbon depletion during rice starch limitation. 相似文献
38.
Purification and characterization of hydrolase with chitinase and chitosanase activity from commercial stem bromelain 总被引:4,自引:0,他引:4
A hydrolase with chitinase and chitosanase activity was purified from commercial stem bromelain through sequential steps of SP-Sepharose ion-exchange adsorption, HiLoad Superdex 75 gel filtration, HiLoad Q Sepharose ion-exchange chromatography, and Superdex 75 HR gel filtration. The purified hydrolase was homogeneous, as examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme exhibited chitinase activity for hydrolysis of glycol chitin and 4-methylumbelliferyl beta-D-N,N',N' '-triacetylchitotrioside [4-MU-beta-(GlcNAc)(3)] and chitosanase activity for chitosan hydrolysis. For glycol chitin hydrolysis, the enzyme had an optimal pH of 4, an optimal temperature of 60 degrees C, and a K(m) of 0.2 mg/mL. For the 4-MU-beta-(GlcNAc)(3) hydrolysis, the enzyme had an optimal pH of 4 and an optimal temperature of 50 degrees C. For the chitosan hydrolysis, the enzyme had an optimal pH of 3, an optimal temperature of 50 degrees C, and a K(m) of 0.88 mg/mL. For hydrolysis of chitosans with various N-acetyl contents, the enzyme degraded 30-80% deacetylated chitosan most effectively. The enzyme split chitin or chitosan in an endo-manner. The molecular mass of the enzyme estimated by gel filtration was 31.4 kDa, and the isoelectric point estimated by isoelectric focusing electrophoresis was 5.9. Heavy metal ions of Hg(2+) and Ag(+), p-hydroxymercuribenzoic acid, and N-bromosuccinimide significantly inhibited the enzyme activity. 相似文献
39.
不同年代铅锌矿渣中细菌的重金属和抗生素抗性特征 总被引:1,自引:1,他引:1
利用主成分分析法,研究了不同年代铅锌矿渣堆化学性质的改变同细菌群体重金属和抗生素抗性特性的关系:结果表明,随堆积年代的延长,矿渣堆5~10cm和25~30cm层面的化学性质差异增加。与这种空间上的环境因子分化相对应,312株随机分离的细菌菌株和97株节杆菌菌株在5种重金属和4种抗生素的抗性比例上也发生了变化:堆积时间在80a左右的C矿渣抗性菌株比例同较年轻的矿渣A(约10a)、B(约20a)有较大差别,但有趣的是矿渣A和矿渣C在层面上的差异都较矿渣B大: 相似文献
40.
钱畅 《信阳农业高等专科学校学报》2013,23(1):11-13
"孝"是人最基本的道德品质,孝德教育是最基本的道德教育。本文分析了大学生孝德现状、问题以及可能的原因,并提出了提高大学生孝德水平的对策。 相似文献