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排序方式: 共有597条查询结果,搜索用时 31 毫秒
31.
Erika Moutinho Costa Tatiana Xavier de CastroFernanda de Oliveira Bottino Rita de Cássia Nasser Cubel Garcia 《Veterinary microbiology》2014
To characterize canine coronavirus (CCoV) circulating in diarrheic puppies in Brazil, 250 fecal samples collected between 2006 and 2012 were tested. By using RT-PCR to partially amplify the M gene, CCoV RNA was detected in 30 samples. Sequence analysis of the M protein grouped eight strains with CCoV-I and another 19 with CCoV-II prototypes. To genotype/subtype the CCoV strains and assess the occurrence of single or multiple CCoV infections, RT-PCR of the S gene was performed, and 25/30 CCoV-positive strains amplified with one or two primer pairs. For 17/25 samples, single infections were detected as follows: six CCoV-I, nine CCoV-IIa and two CCoV-IIb. Eight samples were positive for more than one genotype/subtype as follows: seven CCoV-I/IIa and one CCoV-I/IIb. Sequence analysis revealed that the CCoV-I and IIa strains shared high genetic similarity to each other and to the prototypes. The Brazilian strains of CCoV-IIb displayed an aminoacid insertion that was also described in CCoV-IIb-UCD-1 and TGEV strains. Among the 25 CCoV-positive puppies, five had a fatal outcome, all but one of which were cases of mixed infection. The current study is the first reported molecular characterization of CCoV-I, IIa and IIb strains in Brazil. 相似文献
32.
Valeria F. Del Coco María Alejandra Córdoba Gladys Bilbao Pinto de Almeida Castro Juan Angel Basualdo Mónica Santín 《Veterinary parasitology》2014,199(1-2):112-115
Fecal specimens were obtained from a total of 70 dairy calves less than two months old on 11 municipalities in Buenos Aires, Argentina. After removal of fecal debris by sieving and sucrose flotation, specimens were subjected to PCR to detect the presence of Enterocytozoon bieneusi. PCR revealed a 14.3% of prevalence for E. bieneusi with 10 positive calves from 7 municipalities. Gene sequence analysis conducted in all samples positives by PCR revealed the presence of six genotypes; four previously reported in cattle as well as humans (D, I, J, and BEB4), one never reported in cattle before but previously reported in humans (EbpC), and one novel genotype (BEB10). These results constitute the first molecular characterization of E. bieneusi in Argentina, and suggest a potential risk of zoonotic transmission in this area. 相似文献
33.
Natalia Sevane Hubert Leveziel Geoffrey R Nute Carlos Sanudo Alessio Valentini John Williams Susana Dunner the GeMQual Consortium 《畜牧与生物技术杂志(英文版)》2014,(2):154-162
Background: Consuming moderate amounts of lean red meat as part of a balanced diet valuably contributes to intakes of essential nutrients, in this study, we merged phenotypic and genotypic information to characterize the variation in lipid profile and sensory parameters and to represent the diversity among 15 cattle populations. Correlations between fat content, organoleptic characteristics and lipid profiles were also investigated. Methods: A sample of 436 largely unrelated purebred bulls belonging to 15 breeds and reared under comparable management conditions was analyzed. Phenotypic data -including fatness score, fat percentage, individual fatty acids (FA) profiles and sensory panel tests- and genotypic information from 11 polymorphisms was used. Results: The correlation coefficients between muscle total lipid measurements and absolute vs. relative amounts of polyunsaturated FA (PUFA) were in opposite directions. Increasing carcass fat leads to an increasing amount of FAs in triglycerides, but at the same time the relative amount of PUFAs is decreasing, which is in concordance with the negative correlation obtained here between the percentage of PUFA and fat measurements, as well as the weaker correlation between total phospholipids and total lipid muscle content compared with neutral lipids. Concerning organoleptic characteristics, a negative correlation between fiavour scores and the percentage of total PUFA, particularly to n-6 fraction, was found. The correlation between juiciness and texture is higher than with flavour scores. The distribution of SNPs plotted by principal components analysis (PCA) mainly reflects their known trait associations, although influenced by their specific breed allele frequencies. Conclusions: The results presented here help to understand the phenotypic and genotypic background underlying variations in FA composition and sensory parameters between breeds. The wide range of traits and breeds studied, along with the genotypic information on polymorphisms previo 相似文献
34.
35.
[目的]比较不同基因型特色烤烟品种的烟叶油分表征化学物质和常规化学成分含量的差异.[方法]基于对不同基因型烤烟烟叶油分表征化学物质和常规化学成分差异的探索,以毕纳1号、云烟87、K326和南江3号4个烤烟品种为研究对象,分析了不同基因型烤烟烟叶油分表征物质和常规化学成分含量的差异.[结果]试验表明,云烟87和南江3号的烟叶油分表征化学物质总体好于K326和毕纳1号,云烟87、毕纳1号、K326和南江3号烟叶含钾量均偏低,云烟87、毕纳1号和K326的上部叶烟碱含量高,南江3号和云烟87的中、上部叶还原糖和总糖含量相对较高.[结论]研究可为烟叶质量偏低、油分差的烟区选育和推广优良烤烟品种提供技术支撑. 相似文献
36.
GGE叠图法─分析品种×环境互作模式的理想方法 总被引:6,自引:1,他引:6
本文介绍一种分析作物区域试验结果的方法-GGE叠图法。首先,将原始产量数据减去各地 点的平均产量,由此形成的数据集只含品种主效应G和品种-环境互作效应GE,合称为GGE。对GGE 作单值分解,并以第一和第二主成分近似之。按照第一和第二主成分值将各品种和各地点放到一个平 面图上即形成GGE叠图。借助于辅助线,可以直观回答以下问题:(1)什么是某一特定环境下最好的 品种;(2)什么是某一特定品种最适合的环境;(3)任意两品种在各环境下的表现如何;(4)试验中品 种×环境互作的总体模式是怎样的;(5)什么是高产、稳产品种;(6)什么是有利于筛选高产、稳产品 种的环境。 相似文献
37.
用不同基因型的冬小麦品种花药在W142培养基(改进的W14培养基)上获得较高的出愈率,但不曲因型之间仍存在着显著的差异。用Pharmacia公司PhastSystem电泳仪对不同基因型小麦花药及其愈伤组织蛋白质进行等电聚焦电泳和SDS-聚丙烯酰胺凝胶电泳分析,观察到不同基因型花药蛋白质之间存在着差异,并且初步认为这种蛋白质差异与出愈率有相关性。不同基因型花药愈伤组织之间观察不到明显的带型区别,但它 相似文献
38.
基因型和供体植株生长环境对大白菜游离小孢子胚胎发生的影响 总被引:44,自引:4,他引:44
17个用于大白菜常规育种的基因型在NLN-13液体培养基中进行游离小孢子培养,结果有16个基因型经由小孢子胚胎发生途径获得小孢子胚。这些基因型包括从早熟晚熟的各种类型。各基因之间在小孢子胚胎发生频率方面存在很大差异,产量最高的两个基因型T11和CC11,平均每百花蕾分别达35928和34132个胚。供体植株生长环境对小孢子胚胎发生具有明显影响;在10/20℃(液/昼)的部分控温温室生长的供体植株, 相似文献
39.
TheA-value method, involving the application of a higher15N rate to a reference non-N2-fixing plant, was used to assess the magnitude of N2 fixation in two bambara groundnut cultivars at four growth stages [vegetative, 0–47 days after planting (DAP); early pod-filling, 47–99 DAP; mid-pod-filling, 99–120 DAP; physiological maturity, 120–148 DAP). The cultivars were Ex-Ada, a bunchy type, and CS-88-11, a slightly spreading type. They were grown on a loamy sand. Uninoculated Ex-Ada and CS-88-11 were used as reference plants to measure the N2 fixed in the inoculated bambara groundnuts. In this greenhouse study, soil was the major source of N in bambara groundnuts during vegetative growth, and during this period it accounted for over 80% of the N accumulaed in the plants. However, N2 fixation became the major source of plant N during reproductive growth. There were significant differences between the two cultivars in the ability to fix N2, and at physiological maturity, almost 75% of the N in CS-88-11 was derived from the atmosphere compared to 55% in Ex-Ada. Also, the total N fixed in CS-88-11 at physiological maturity was almost double that in Ex-Ada. Our data indicate that the higher N2 fixation in CS-88-11 was due to two factors, a higher intensity of N2 fixation and a longer active period of N2 fixation. The results also suggest that bambara groundnut genotypes could be selected for higher N2 fixation in farining systems. 相似文献
40.
高产节水小麦基因型生理特性及综合评价 总被引:15,自引:0,他引:15
应用4个年度的研究资料,综合分析了高产节水小麦基因型的生理特性。研究表明,叶水势、气孔阻力、蒸腾强度和离体叶片失水速率品种间均存在明显差异。根据最高产量、少水/足水产量比、叶水势、气孔阻力、蒸腾强度和离体叶片失水速率提出了综合评价高产节水小麦基因型的标准。 相似文献