Salinity and sodicity effects on respiration and microbial biomass of soil   总被引：4，自引：2，他引：2  

Vanessa N. L. Wong  Richard S. B. Greene 《Biology and Fertility of Soils》2008,44(7):943-953

An understanding of the effects of salinity and sodicity on soil carbon (C) stocks and fluxes is critical in environmental management, as the areal extents of salinity and sodicity are predicted to increase. The effects of salinity and sodicity on the soil microbial biomass (SMB) and soil respiration were assessed over 12weeks under controlled conditions by subjecting disturbed soil samples from a vegetated soil profile to leaching with one of six salt solutions; a combination of low-salinity (0.5dSm⁻¹), mid-salinity (10dSm⁻¹), or high-salinity (30dSm⁻¹), with either low-sodicity (sodium adsorption ratio, SAR, 1), or high-sodicity (SAR 30) to give six treatments: control (low-salinity low-sodicity); low-salinity high-sodicity; mid-salinity low-sodicity; mid-salinity high-sodicity; high-salinity low-sodicity; and high-salinity high-sodicity. Soil respiration rate was highest (56–80mg CO₂-C kg⁻¹ soil) in the low-salinity treatments and lowest (1–5mg CO₂-C kg⁻¹ soil) in the mid-salinity treatments, while the SMB was highest in the high-salinity treatments (459–565mg kg⁻¹ soil) and lowest in the low-salinity treatments (158–172mg kg⁻¹ soil). This was attributed to increased substrate availability with high salt concentrations through either increased dispersion of soil aggregates or dissolution or hydrolysis of soil organic matter, which may offset some of the stresses placed on the microbial population from high salt concentrations. The apparent disparity in trends in respiration and the SMB may be due to an induced shift in the microbial population, from one dominated by more active microorganisms to one dominated by less active microorganisms.  相似文献   

Reproducible infection model for Clostridium perfringens in broiler chickens     

Pedersen K  Bjerrum L  Heuer OE  Lo Fo Wong DM  Nauerby B 《Avian diseases》2008,52(1):34-39

Experiments were carried out to establish an infection and disease model for Clostridium perfringens in broiler chickens. Previous experiments had failed to induce disease and only a transient colonization with challenge strains had been obtained. In the present study, two series of experiments were conducted, each involving four groups of chickens with each group kept in separate isolators. A coccidial vaccine given at 10 times the prescribed dosage was used to promote the development of necrotic enteritis. In the first experiment, cultures of C. perfringens were mixed with the feed at day 9, 10, 11, and 12, and the coccidial vaccine was given at day 10, whereas in the second experiment, C. perfringens cultures were mixed with the feed at day 17, 18, 19, and 20, and the coccidial vaccine was given at day 18. Chickens were examined at day 9, 11, 12, and 15 (Experiment 1), and at day 17, 18, 20, and 24 (Experiment 2). There was no mortality in any of the groups; however, chickens in the groups receiving both coccidial vaccine and C. peifringens developed the subclinical form of necrotic enteritis, demonstrated by focal necroses in the small intestine, whereas chickens in control groups or groups receiving only coccidial vaccine or only C. perfringens cultures developed no necroses. The results underline the importance of predisposing factors in the development of necrotic enteritis.  相似文献   

Identification of a novel Bacillus species isolated from Calculus Bovis     

Tien‐Chun WAN  Fu‐Yuan CHENG  Yu‐Tse LIU  Chao‐Ming WANG  Ching‐Lin SHYU  Chih‐Ming CHEN  Liang‐Chuan LIN  Ryoichi SAKATA 《Animal Science Journal》2008,79(6):693-698

A novel Bacillus species of Calculus Bovis (cow gallstone) was isolated and identified in this study. Morphological features, bacterial fatty acid analysis using a microbial identification system, carbon source utilization profiles using Biolog system and 16S rDNA sequencing were employed to identify the isolated bacterium. This isolated bacterium was observed to be Gram‐negative, aerobic growing, rod‐shaped and short chain. The results of bacterial fatty acid analysis and physiological characteristics were not matched to the database. The main fatty acids found in the bacterium were 65.96% branched chain saturated fatty acids (iso C_11:0, anteiso C_11:0 and iso C_13:0～anteiso C_19:0). The bacterium oxidized 35 carbon sources and weakly responded with 49 of the 95 different carbon sources analyzed with the Biolog identification system. Based on 16S rDNA sequence analysis, this bacterium was classified as a novel Bacillus species.  相似文献   

Seroepidemiology and genotyping of hepatitis E virus in Singapore reveal rise in number of cases and similarity of human strains to those detected in pig livers     

Chui Ching Wong  Su Ming Thean  Youming Ng  Joanne Su Lin Kang  Tong Yong Ng  Man Ling Chau  Tse Hsien Koh  Kwai Peng Chan 《Zoonoses and public health》2019,66(7):773-782

Hepatitis E virus (HEV) causes 20 million infections worldwide yearly, of which only about 3.3 million are symptomatic. In developed Asian countries, HEV strains detected in human sera and in food sources were genetically similar, suggesting that indigenous HEV infections may be largely food‐borne. To assess the burden of hepatitis E in Singapore, we performed a seroepidemiologic study of the infection. Additionally, we carried out HEV genotyping on archived, residual HEV IgM‐positive serum samples collected between 2014 and 2016 (n = 449), and on pig liver samples (n = 36) purchased from wet markets and supermarkets. Our study shows a rise in hepatitis E incidence (IgM) from 1.7 to 4.1 cases per 100,000 resident population from 2012 to 2016 and an increase in hepatitis E IgG positivity rate among residents from 14% in 2007 to 35% in 2016. Other findings also suggest the epidemiology of hepatitis E in Singapore has shifted, from it being mainly a disease imported from the Indian subcontinent, to one that is now increasingly prevalent in our resident population. Genotypes obtained from 143 human samples identified the majority to be genotype 3 (n = 121), 21 to be genotype 1 and one to be genotype 4. Further phylogenetic analyses suggest genotype 3a to be the cause of indigenous infections in residents, which showed genetic similarity to the genotype 3a strains detected in pig livers. This link between the strains in the majority of human samples and those in pig livers consumed by the public suggests a possible food‐borne route of HEV infection in Singapore.  相似文献   

Polymerase chain reaction for antigen receptor rearrangement: Benchmarking performance of a lymphoid clonality assay in diverse canine sample types     

E. J. Ehrhart  Shukmei Wong  Keith Richter  Victoria Zismann  Carolyn Grimes  William Hendricks  Chand Khanna 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(3):1392-1402

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Discriminatory features of acute eosinophilic dermatitis with oedema (Wells‐like syndrome) and sterile neutrophilic dermatosis (Sweet's‐like syndrome) in dogs     

Charles W. Bradley  Christine L. Cain  Talia S. Wong  Jacquelyn D. Ferracone  Kyle H. Goldschmidt  Elizabeth A. Mauldin 《Veterinary dermatology》2019,30(6):517-e157

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家蚕（Bombyxmori）全基因组框架图   总被引：27，自引：0，他引：27  

夏庆友  周泽扬  鲁成  程道军  代方银  李斌  赵萍  查幸福  程廷才  柴春利  潘国庆  许金山  刘春  林英  钱吉凤  侯勇  吴正理  李关荣  潘敏慧  李春峰  沈以红  蓝希钳  袁联伟  李田  徐汉福  杨光伟  万永继  朱勇  余茂德  沈卫德  吴大洋  向仲怀  于军  王俊  李瑞强  石剑萍  李恒  李光远  苏建宁  王晓玲  李国庆  张增金  吴清发  李俊  张庆鹏  韦宁  徐建哲  孙海波  董乐  刘东源  赵胜利  赵晓兰  孟庆顺  兰锋镝  黄显刚  李源哲  方林  李昌锋  李大为  孙永巧  张振鹏  杨峥  黄艳清  奚艳  亓秋辉  贺丹丹  黄海燕  张晓伟  王智强  李文杰  曹玉竹  余迎朴  俞鸿  李金宏  叶杰华  陈欢  周雁  刘斌  王晶  叶葭  纪海  李胜霆  倪培相  张建国  张勇  郑洪坤  毛炳宇  王文  叶辰  李松岗  汪建  杨焕明 《蚕学通讯》2008,28(4):1-16

我们在此报告了家蚕（Bombyxmori）的基因组序列框架图,它覆盖了所有已知家蚕基因的90．9％。我们估计的基因数是18510,超过黑腹果蝇报道的13379个基因。我们将家蚕基因组与果蝇、蚊子、蜘蛛和蝴蝶等进行了比较分析,揭示了它们在基因组成上同时具有相似性和差异性。  相似文献   

Evidence‐based veterinary dermatology: a review of published studies of treatments for Otodectes cynotis (ear mite) infestation in cats          下载免费PDF全文

Ching Yang  Hui‐Pi Huang 《Veterinary dermatology》2016,27(4):221-e56

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Purification and localization of nitric oxide synthases from hybrid tilapia (Nile tilapia x Mozambique tilapia)     

Wang WS  Hung SW  Lin YH  Tu CY  Wong ML  Chiou SH  Shieh MT 《Journal of aquatic animal health》2007,19(3):168-178

The aims of this study were to purify and localize the nitric oxide synthases (NOSs) from hybrid tilapia (Nile tilapia Oreochromis niloticus x Mozambique tilapia O. mossambicus). The purification procedures involved affinity chromatography with a 2', 5'-ADP-agarose 4B column and ion exchange with a diethylaminoethanol Bio-Gel A column. The results from gel filtration assays showed that the molecular weights of neuronal NOS (nNOS) and inducible NOS (iNOS) were 178 and 120 kDa, respectively. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis results showed that there were three bands with molecular weights of 89, 47, and 29 kDa from the purified nNOS. However, only one band, with a molecular weight of 120 kDa, appeared on the gel from the purified iNOS. Hybrid tilapia nNOS was a dimer structure, while iNOS appeared to be a monomer structure. Moreover, our results revealed that the activities of nNOS and iNOS were significantly higher after the addition of Ca+2 or Mg+2 ions individually. However, when L-arginine and NADPH were present, the addition of 1 mM of either ion did not further increase the activity. The chemical L-N(G)-methyl-L-arginine could inhibit the activities of the purified NOSs with or without L-arginine. Western blot analyses showed only an 89-kDa immunoreactive band from the extracts of cerebrum; however, we did not find the specific bands in other tissues, such as gill, intestine, liver, spleen, and anterior kidney. We found another 120-kDa immunoreactive protein band with the rabbit antirat iNOS serum against iNOS from the extracts of anterior kidney and spleen. The results of immunohistochemistry with the rabbit antihuman nNOS serum indicated that the nNOS existed in the cerebellum, olfactory bulb, diencephalons, and nerve cell bodies and neuronal fibers of the spinal cord. Interestingly, only macrophages from anterior kidney and spleen showed positive reactions with the rabbit antirat iNOS serum. In the same way, the endothelial NOS (eNOS) located in the heart and epithelial cells of the blood vessels reacted positively with the rabbit antibovine eNOS serum.  相似文献   

Dandy-Walker-Like syndrome in a quarter horse colt     

Wong D  Winter M  Haynes J  Sponseller B  Schleining J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(5):1130-1134

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