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81.
MAO Qian-qian ZHOU Ling TANG Qing-hai BU Bin TANG Cun-duo JIAO Zhu-jin YAO Lun-guang KAN Yun-chao YANG Jian-wei CUI Shang-jin 《中国畜牧兽医》2016,43(7):1659-1666
This study was aimed to prepare canine parvovirus (CPV) VP2 protein polyclonal antibody.The recombinant expression vector pET28a-CPV-VP2 was constructed and transfromed into E.coli BL21 (DE3),the expression of recombinant proteins was induced by IPTG from which the fusion protein was identified by SDS-PAGE.The target protein was purified and emulsify with adjuvant,the prepared immunogen was inoculated into rabbit by subcutaneous injections to prepare of VP2 protein specific polyclonal antibody.The immuno-activity,titers,neutralization titers of the prepared polyclonal antibody were determined by immunoperoxidase monolayer assay (IPMA).The results showed that the expressed recombinant protein VP2 (rVP2) existed in the form of inclusion body with a molecular weight of 72 ku.The prepared polyclonal antibody titer was 1 600 dilution,the virus titer was 107 TCID50/mL,the neutralizing titer was 1∶2 884.The antibodies showed specific reaction with CPV.In conclusion,rVP2 specific polyclonal antibody showed wonderful immunocompetence,specificity and neutralizing activity,providing foundation for the development of genetic vaccine and clinical therapeutic method. 相似文献
82.
The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage 下载免费PDF全文
Yan‐Su Wang Wei Shi Lin‐Ting Huang Cheng‐Long Ding Chuan‐Chao Dai 《Animal Science Journal》2016,87(4):525-535
Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials. 相似文献
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85.
以18种秋海棠属植物为试材,基于叶绿体ndhA基因内含子片段,利用Codon Code Aligner软件拼接序列后,通过MEGA软件进行比对并计算19个秋海棠属植物种间及种内遗传距离,最后利用邻接法构建分子系统树,研究了该片段作为DNA条形码对秋海棠属植物进行物种鉴定的可行性。结果表明:秋海棠属19个种类共59个个体的ndhA基因内含子序列长度为1 182bp,在所考察的候选秋海棠属植物中具有最大的种间变异和较小的种内变异,且二者存在极显著差异。在系统树中,秋海棠属植物每一物种能够分别形成各自独立的分支,表现出良好单系性。基于ndhA基因内含子的DNA条形码在识别秋海棠属植物物种方面和传统形态学基本一致。该研究表明,以ndhA基因内含子作为秋海棠属植物DNA条形码进行物种鉴定具有一定的可行性。 相似文献
86.
为探讨不同欧洲型黄瓜种质资源对高温的适应性差异,为耐热种质资源筛选及耐热机理的深入研究提供理论和实践依据,以20份欧洲型黄瓜的叶片为材料,设置6个高温处理,以室温为对照,测定浸提液电导率值并计算相对电导率,通过拟合Logistic方程,计算半致死温度(LT50)。试验结果表明,随着温度升高,相对电导率呈"S"型曲线,且相对电导率与处理温度存在显著的直线相关关系,通过计算"S"型曲线拐点求得20份欧洲型黄瓜的半致死温度在45~51℃,其中33-2的半致死温度最高,达到50.09℃,37-1的半致死温度最低,为45.82℃。20份欧洲型黄瓜的耐高温能力由强到弱依次为33-275-232-233-111-231-209-236-276-136-137-210-135-276-211-143-235-175-132-137-1。因此,半致死温度可作为评价欧洲型黄瓜耐热性的一个可靠指标。 相似文献
87.
Long MT Gibbs EP Mellencamp MW Zhang S Barnett DC Seino KK Beachboard SE Humphrey PP 《Equine veterinary journal》2007,39(6):486-490
REASON FOR PERFORMING STUDY: West Nile virus (WNV) infection is endemic and able to cause disease in naive hosts. It is necessary therefore to evaluate the safety of new vaccines. OBJECTIVES: To establish: 1) the safety of a modified live Flavivirus/West Nile virus (WN-FV) chimera by administration of an overdose and testing for shed of vaccine virus and spread to uninoculated sentinel horses; 2) that this vaccine did not become pathogenic once passaged in horses; and 3) vaccine safety under field conditions. METHODS: There were 3 protocols: 1) In the overdose/shed and spread study, horses were vaccinated with a 100x immunogenicity overdose of WN-FV chimera vaccine and housed with sentinel horses. 2) A reversion to virulence study, where horses were vaccinated with a 20x immunogenicity overdose of WN-FV chimera vaccine. Horses in both studies were evaluated for abnormal health conditions and samples obtained to detect virus, seroconversion and dissemination into tissues. 3) In a field safety test 919 healthy horses of various ages, breeds and sex were used. RESULTS: Vaccination did not result in site or systemic reactions in either experimental or field-injected horses. There was no shed of vaccine virus, no detection of vaccine virus into tissue and no reversion to virulence with passage. CONCLUSIONS: WN-FV chimera vaccine is safe to use in horses with no evidence of ill effects from very high doses of vaccine. There was no evidence of reversion to virulence. In addition, administration of this vaccine to several hundred horses that may have been previously exposed to WNV or WNV vaccine resulted in no untoward reactions. POTENTIAL RELEVANCE: These studies establish that this live attenuated Flavivirus chimera is safe to use for immunoprophylaxis against WNV disease in horses. 相似文献
88.
Long MT Gibbs EP Mellencamp MW Bowen RA Seino KK Zhang S Beachboard SE Humphrey PP 《Equine veterinary journal》2007,39(6):491-497
REASON FOR PERFORMING STUDY: West Nile virus (WNF) is a Flavivirus responsible for a life-threatening neurological disease in man and horses. Development of improved vaccines against Flavivirus infections is therefore important. OBJECTIVES: To establish that a single immunogenicity dose of live Flavivirus chimera (WN-FV) vaccine protects horses from the disease and it induces a protective immune response, and to determine the duration of the protective immunity. METHODS: Clinical signs were compared between vaccinated (VACC) and control (CTRL) horses after an intrathecal WNV challenge given at 10 or 28 days, or 12 months post vaccination. RESULTS: Challenge of horses in the immunogenicity study at Day 28 post vaccination resulted in severe clinical signs of WNV infection in 10/10 control (CTRL) compared to 1/20 vaccinated (VACC) horses (P<0.01). None of the VACC horses developed viraemia and minimal histopathology was noted. Duration of immunity (DPI) was established at 12 months post vaccination. Eight of 10 CTRL exhibited severe clinical signs of infection compared to 1 of 9 VACC horses (P<0.05). There was a significant reduction in the occurrence of viraemia and histopathology lesion in VACC horses relative to CTRL horses. Horses challenged at Day 10 post vaccination experienced moderate or severe clinical signs of WNV infection in 3/3 CTRL compared to 5/6 VACC horses (P<0.05). CONCLUSIONS: This novel WN-FV chimera vaccine generates a protective immune response to WNV infection in horses that is demonstrated 10 days after a single vaccination and lasts for up to one year. POTENTIAL RELEVANCE: This is the first USDA licensed equine WNV vaccine to utilise a severe challenge model that produces the same WNV disease observed under field conditions to obtain a label claim for prevention of viraemia and aid in the prevention of WNV disease and encephalitis with a duration of immunity of 12 months. 相似文献
89.
收获期对玉米茎秸产量和营养价值的影响 总被引:1,自引:1,他引:0
研究适于云南亚热带地区的玉米品种.结果表明:玉米青秸产量以蜡熟期最高,干秸产量以完熟期最高;粗蛋白质产量和产奶净能量(NEL)均以蜡熟期最高;专用青贮玉米、粮饲玉米和普通玉米蜡熟期鲜秸产量分别为108.9、111.7和127.5 t/hm2,干秸产量为33.4、36.4和40.7 t/hm2,粗蛋白质产量为2.7、2.9和3.4 t/hm2,产奶净能量为49825.8、57789.4和64430.3 Mcal/t/hm2;高产优质玉米品种为京科9号、樱红和路单4号. 相似文献
90.
Jie Li Rongyue Zhang Yinhu Li Chaohua Long Wengfeng Li Hongli Shan Wenjie Lu Yingkun Huang 《Plant pathology》2023,72(1):89-99
Brown stripe disease is a severe foliar fungal disease of sugarcane worldwide and is widespread in all sugarcane planting areas in China. Brown stripe is a major disease that seriously affects the output and quality of the sugarcane industry in Yunnan Province, China's second-largest sugar base, while the pathogen of this disease remains not yet fully understood. To address this, we isolated and identified the fungi associated with 68 leaf samples showing typical symptoms of brown stripe from 22 sugarcane varieties in different areas of Yunnan Province. A total of 113 isolates were obtained, which were morphologically similar. Of these, 64 representative isolates were sequenced for the internal transcribed spacer region (ITS), GAPDH and EF-1α loci. All representative isolates grouped with the type strain of Bipolaris setariae in the phylogenetic trees inferred with individual and concatenated sequences of ITS, GAPDH and EF1-α. Pathogenicity test results showed that B. setariae strains were able to induce typical symptoms of brown stripe. The results obtained in this study clarify that only B. setariae is associated with sugarcane brown stripe in Yunnan, China. It is recorded here for the first time as a pathogen causing sugarcane brown stripe in Yunnan, and it is able to infect many major cultivars and new varieties, posing a new threat to the sugar industry in Yunnan Province. In addition, these results provide the scientific basis for the future breeding of disease-resistant varieties and effective prevention and control of sugarcane brown stripe disease. 相似文献