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61.
猪瘟和猪支原体肺炎是两种较为常见的猪传染病,首免日龄接近,本试验通过对24头30—40日龄仔猪分别或同时免疫猪支原体肺炎活疫苗(RM48株)和猪瘟活疫苗(传代细胞源),研究其相互之间是否存在免疫干扰。试验结果显示,两种疫苗同时免疫对其各自的近期免疫效力均无明显影响。  相似文献   
62.
对鸡毒支原体(MG)SJ株的生物学特性及结构蛋白进行分析,试验结果表明该菌株易于猪血清培养基中生长,并经5次传代后生长趋于稳定。与F株比较,SJ株对鸡胚气管环纤毛的损伤更为严重。SDS-PAGE图谱显示SJ、F和PG31之间的蛋白条带略有差异,暗示了结构蛋白的这些细微变化可能是MG致病的重要因素。  相似文献   
63.
The occurrence of Mycoplasma hyosynoviae at different locations of the upper respiratory tract and tonsils of pigs was investigated in herds with problems of arthritis apparently caused by this microorganism. The isolation of M. hyosynoviae was facilitated by the use of a medium selectively suppressing the growth of Mycoplasma hyorhinis. M. hyosynoviae was cultured from 106 of 178 tonsils of slaughterhouse pigs from 8 herds but could not be isolated from the mucosa of the nasal cavity or the oral-pharyngeal area of 100 living, 10-20 weeks old pigs in 5 of the herds. The value of the selective principles in the medium appears from the circumstance that 86 of the 106 isolates were obtained despite the presence of M. hyorhinis. It is concluded that the tonsil is a reservoir for M. hyosynoviae and is probably the location of choice for an easy demonstration of the presence of this mycoplasma in a pig herd.  相似文献   
64.
Sodium-dodecyl-sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was used to study the protein variability of Mycoplasma hyopneumoniae isolates. Fifty-six M. hyopneumoniae isolates from 6 different countries and 37 different herds were used. From eight herds, more than one isolate was available. All SDS-PAGE patterns of isolates originating from different herds were clearly divergent. Intra-species protein variability was quantified using the reference strain J and seven field strains all obtained from different herds and classified according to virulence. Between the field strains, a variability of 25% was found, while the culture-adapted strain J was clearly divergent and showed 30% variability with the field strains. No clustering according to virulence was obtained, but a protein band of about 181 kDa was present in the two highly virulent isolates whereas this protein band was absent in the moderately and low virulent isolates. Protein patterns of isolates derived from different animals from the same herd, were identical or differed in only a few protein bands. This study clearly indicates that, in agreement with previous studies on genomic diversity of M. hyopneumoniae isolates, proteomic variability within the species is high. Our study did not find clear evidence that more than one M. hyopneumoniae isolate circulates within a herd at a specific time point. The minor differences found between M. hyopneumoniae isolates from the same herd might reflect the organism's ability to alter its proteomic expression profile under field conditions.  相似文献   
65.
猪肺炎霉形体膜上ATP酶基本性质的研究   总被引:1,自引:0,他引:1  
本文测定了猪肺炎霉形体膜上ATP酶的活性,同时就温度、pH及一些金属离子对该ATP酶活性的影响进行了研究。结果表明:猪肺炎霉形体膜上ATP酶比活力为9.232左右。在25~40℃温度范围内酶活性较稳定。pH适应范围为6.5~8之间,以pH7.6为最适。Mg2+、Mn2+、Zn2+对酶均有一定程度的激活作用,而Ca2+、Na+-K+具有不同程度的抑制作用。  相似文献   
66.
为了解猪肺炎支原体对抗菌药物的敏感性,采用宏量肉汤稀释法对4株猪肺炎支原体的最小抑菌浓度(MIC)值进行了测定。结果表明,猪肺炎支原体对泰妙菌素和环丙沙星最为敏感,MIC≤0.03μg/mL,其次分别为四环素类药物(包括四环素和多西环素)、林可霉素和泰乐菌素,而对氟苯尼考的敏感性则较差。本研究可为猪支原体肺炎的防控以及抗菌药物的合理使用提供参考。  相似文献   
67.
Summary

Since the macroscopical and microscopical examination of bull semen does not in all cases appear to give conclusive indications concerning the fertilizing capacity, an investigation of some biochemical parameters was undertaken. It was shown that the following biochemical examination could furnish some more information about the quality of the semen: 1. Determination of the phenylalanine‐ α‐ketoglutarate transaminase activity both in the seminal plasma and in the whole semen. A high transaminase activity in the plasma points to leakage out of the spermatozoa, thus indicating an affection of the spermatozoa. In that case larger amounts of basic amino acids and of leucine were often found in the seminal plasma than would normally be observed.

2. Gas chromatographic examination of the steroids occurring both in the seminal plasma and in the spermatozoa. In a number of infertile bulls small peaks of progesterone were found together with those of other, unidentified compounds.

3. Investigation of the carbohydrate metabolism in the semen. In a number of fertile bulls the following deviations were found: a. the presence of quite a lot of fructose in the spermatozoa;

b. the presence of glucuronic acid and / of other foreign compounds in the spermatozoa or in the plasma;

c. an elevated pH in the seminal plasma some 2 to 3 hours after ejaculation;

d. a low phenylalanine‐α ‐ketoglutarate transaminase activity in the whole semen (the spermatozoa had been disrupted by freezing).

4. Investigation of the presence of reducing aldehydes (glycolaldehyde and glyceraldehyde) inside the spermatozoa.

The determinations mentioned under 1, 3c and 3d can easily be carried out in the laboratories of each District Animal Health Service and of the A.I. stations; the same is true of the occurrence of amino acids in the seminal plasma and of fructose and aldehydes inside the spermatozoa if facilities are available for electrophoresis and chromatography.  相似文献   
68.
目的 优选人参药性菌质中总皂苷的最佳提取工艺条件.方法 通过单因素考察、正交试验考察,确定最佳工艺条件.以总皂苷含量为指标,采用紫外可见分光光度法测定.结果 人参药性菌质最佳提取条件为加7倍量50%乙醇,回流提取2次,每次1.5小时.结论 优选出的提取工艺简单,效率高,成本较低,可适用于大生产.  相似文献   
69.
赵爱云  何强  井波 《安徽农业科学》2011,39(14):8619-8621
[目的]掌握阿拉尔垦区猪嗜血支原体的流行现状。[方法]根据GenBank上发表的猪嗜血支原体16S rRNA基因组序列(U88565)设计1对特异性引物,对采自新疆阿拉尔垦区的样品进行PCR扩增,并将其产物克隆到pBR322载体后测序。[结果]扩增出的片段为0.836 kb。同源性分析结果表明,该序列与猪嗜血支原体参考基因组序列同源性为99.47%,反映出我国分离株与国外株基因同源性较高。[结论]建立了一种猪嗜血支原体PCR检测方法,该方法为猪嗜血支原体病的快速诊断及流行病学调查提供了新的手段,并为相关基因的表达及功能研究奠定了基础。  相似文献   
70.
本研究旨在建立联合检测胸膜肺炎放线杆菌、猪肺炎支原体和多杀性巴氏杆菌的DNA芯片.用7个从3种病菌基因组中扩增出的不同特异性靶DNA制作基因芯片,并对芯片的靶DNA和探针浓度、杂交温度、重复性、特异性和灵敏度进行了研究.结果表明,检测芯片的特异性强,能与测试的李氏放线杆菌、猪鼻支原体和副猪嗜血杆菌等9种病原区分;灵敏度高,在50μL标记反应体系中,能检测到10~50 pg基组DNA,芯片可重复利用.用芯片对44株目标菌的不同型标准菌株、分离株和疫苗株进行了检测.其信号值≥1 000,信号噪音比(SNR)≥6.用芯片对45头病猪和97头健康猪的临床样品选择培养物进行了检测,其检出率分别为多杀性巴氏杆菌71.1%和49.5%、胸膜肺炎放线杆菌42.2%和26.8%、猪肺炎支原体20%和22.7%,混合感染率分别为42.2%和24.7%.在检测临床样品时,芯片法与PCR的符合率为97.8%~100%,与分离鉴定法的符合率为87.6%~95.6%.研究表明,研制的芯片特异性强、敏感性高、可重复使用,是一种能有效用于胸膜肺炎放线杆菌、猪多杀性巴氏杆菌和猪肺炎支原体鉴定和联合检测的新工具.  相似文献   
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