4株酸奶噬菌体的分离     

徐成勇  吴昊  顾晓琳  何楚莹  陶仲炎  秦玉青  周凌华  应杰  诸葛健  郭本恒 《乳业科学与技术》2004,26(4):147-149

从上海光明乳业股份有限公司车间发酵罐中分离出4株酸奶噬菌体。1号噬菌体头部呈六角形，平均直径为95.1nm，头部剖面平均面积为8184．8nm^2，尾部的平均直径为18．3nm，平均长度为403．4nm；2号噬菌体头部呈六角形，平均直径为85．4nm，头部剖面平均面积为8046．2nm^2，尾部的平均直径为23．3nm，平均长度为549．4nm；3号噬菌体头部呈六角形，平均直径为95．5nm，头部剖面平均面积为9792．3nm^2，尾部的平均直径为19．8nm，平均长度为450．5nm；4号噬菌体头部呈六角形，平均直径为119．3nm．头部剖面平均面积为12586．1nm^2，尾部的平均直径为23．6nm，平均长度为520．5nm。  相似文献   

BACTERIAL ENDOCARDITIS WITH THROMBUS FORMATION AND ABSCESSATION IN A HORSE     

Melissa trogdon  Hines  DVM  PhD  Jerry R.  Heidel  DVM  PhD  David D.  Barbee  DVM  MS 《Veterinary radiology & ultrasound》1993,34(1):47-51

A 2.5 year old Appaloosa stallion with progressive weight loss and a heart murmur was diagnosed as having vegetative endocarditis of the right atrioventricular valves with a mass in the right atrium. The ultrasonographic appearance of the lesion was characterized by extreme reverberation. On postmortem examination, a 9 cm diameter thrombus was found within the right atrium and auricle, occupying approximately 80% of the chamber volume. Additionally, a lenticular abscess extended throughout the parietal cusp of the right atrioventricular valve. Histologic examination revealed that the lesions were septic with numerous gram positive cocci in short chains, suggestive of Streptococcus equi , and gram negative rods.  相似文献   

2型猪链球菌的血清学鉴定   总被引：41，自引：0，他引：41  

黄毓茂  黄引贤 《中国兽医学报》1995,15(1):63-65

本试验首次证实了２型猪链球菌在我国的存在，采用玻片凝集、琼脂扩散及毛细管沉淀等３项试验，对１９９０年以来广东某猪场断奶仔猪暴发流行的败血症、脑膜炎及关节炎病猪中分离的１５株链球菌进行了血清学鉴定。结果表明：１５株链球菌均为２型猪链球菌；用高压法提取抗原进行沉淀反应，其结果比酸热法提取抗原具有简便、敏感、特异性强的特点。  相似文献   

The redox potential of growing cultures of Streptococcus bovis Orla-Jensen compared with other facultative anaerobes.     

J Wolstrup  S A Chaudry  V Jensen 《Acta veterinaria Scandinavica》1978,19(4):535-542

The changes of redox potential were measured in growing cultures of three strains of Streptococcus bovis, together with three strains of Staphylococcus aureus and one strain of each of Lactobacillus plantaram, Lactobacillus casei, and Eschericia coli. It was found that both S. aureus and E. coli could reduce the redox potential of the growth medium to very low values (between —400 mv and —600 mv), whereas the streptococci and lactobacilli were able to cause only slight or insignificant changes of the redox potential. Respirometric measurements confirmed that the capacity of oxygen consumption of S. bovis was very small compared to that of E. coli and S. aureus. On this basis the authors conclude that S. bovis in all probability is unable to contribute significantly to maintenance of the low redox potential of its natural habitat, the rumen. This function must be carried out by other bacteria, such as enterobacteria or staphylococci, which are capable of performing a true, aerobic respiration.  相似文献   

猪附红细胞体16S rRNA基因的序列测定和系统进化分析   总被引：11，自引：3，他引：11  

张浩吉  谢明权  张健騑  覃宗华  顾万军  蔡建平 《畜牧兽医学报》2005,36(6):596-601

从确诊为猪附红细胞体感染的猪场，无菌采集血样，抽提猪附红细胞体基因组DNA，采用真细菌的通用引物进行16S rRNA基因扩增，对扩增产物进行克隆和测序。从3个地理位置不同的猪场均成功地扩增出长度为1469bp的核苷酸序列。系统进化分析表明，3个猪场样品所测序列一致性达99．52％以上，具有相同的基因型，但与国外报道的猪附红细胞体Illinois株同源性为95％，属于同一基因群，但基因型不同；所有种类的附红细胞体和血巴尔通氏体组成同一进化分支，这类血营养菌与支原体科，支原体属的病原最靠近(75％)，而与立克次氏体目的病原较远(70％)。上述研究证实，广东所流行的猪附红细胞体是一种新基因型的猪附红细胞体，建议命名为猪附红细胞体广东株型；为反映进化关系，猪附红细胞体和其它血营养菌应划归于支原体科的支原体属。  相似文献   

抗附红细胞体有效药物的筛选   总被引：7，自引：0，他引：7  

郑海红  姚宝安  赵俊龙  周艳琴  冯汉利  付媛  王金苹  刘琴  袁建丰  江涛 《畜牧兽医杂志》2005,24(2):1-3

以PCR检测附红细胞体呈现阳性，且镜检染虫率达909／5以上的猪血样为研究对象，选择几种附红细胞体敏感的药物(血虫净，附红净，庆大霉素，博士914，土霉素，三毒清，红弓链914，附红120，红弓链克，乌金土霉素)和对支原体敏感的恩诺沙星，对立克次氏体敏感的红霉素，采用两种方法进行体外药效试验。附红净对附红细胞体的作用效果最明显，而庆大霉素对附红细胞体基本无效，其他药物对附红细胞体也有一定杀灭效果。  相似文献   

猪附红细胞体感染对仔猪猪瘟免疫效果的影响   总被引：2，自引：0，他引：2  

柴方红  张守发  姜秋杰  贾立军 《畜牧与兽医》2005,37(11):13-15

为探讨猪附红细胞体对仔猪猪瘟免疫效果的影响,本试验利用猪瘟抗体检测ELISA试剂盒,对已注射猪瘟疫苗的69头感染猪附红细胞体的仔猪和31头无猪附红细胞体感染的健康仔猪进行了猪瘟抗体检测。结果表明,感染猪附红细胞体仔猪的猪瘟抗体水平低下,其猪瘟疫苗整体免疫合格率(49·2%)明显低于健康仔猪(93·5%),且显性感染仔猪的免疫合格率(41·6%)明显低于隐性感染仔猪(53·5%)。说明猪附红细胞体严重干扰了猪瘟疫苗的免疫效果,且干扰程度与猪附红细胞体的感染程度呈正相关。  相似文献   

Use of quantitative real‐time PCR to determine viability of Streptococcus equi subspecies equi in respiratory secretions from horses with strangles          下载免费PDF全文

N. Pusterla  C. M. Leutenegger  S. M. Barnum  B. A. Byrne 《Equine veterinary journal》2018,50(5):697-700

  相似文献   

Effects of Inulin Chain Length on Fermentation by Equine Fecal Bacteria and Streptococcus bovis     

《Journal of Equine Veterinary Science》2017

Grass fructans can be fermented by Gram-positive bacteria (e.g., Streptococcus bovis) in the equine hindgut, increasing production of lactic acid and decreasing pH. The degree of polymerization (DP) of fructans has been suggested to influence fermentation rates. The objective of the present study was to determine how DP impacts fermentation by equine fecal bacteria and a model S. bovis. Fecal microbes from three mares were harvested by differential centrifugation, washed, and resuspended in anaerobic media containing short-chain (SC; DP ≤ 10) or long-chain (LC) inulin (DP ≥ 23) from 0% to 2% wt/vol. After 24 hours of incubation (37°C), samples were collected for pH determination. Data were analyzed using the general linear models (GLM) procedure testing for the effect of treatment, concentration, and treatment × concentration (SAS v. 9.3). At all concentrations, the pH was lower in SC fermentations than in LC (P < .0001, in all cases). To determine the effect of DP on S. bovis, cultures were grown (39°C, 9 hours) with 0.1%, 0.5%, or 1.3% SC or LC inulin. Optical density (600 nm) was determined by spectrophotometry. Maximum specific growth rates (μ) were determined by linear regression (2–5 hours). Data were analyzed using the one-way analysis of variance procedure (SAS v. 9.3). The final optical density (600 nm), μ, and yield were higher with SC than with LC fermentation (P < .05). These results indicate that SC inulin may be more available for fermentation than LC inulin by equine fecal bacteria and S. bovis, specifically.  相似文献   

猪链球菌蛋白表面展示系统的构建及展示蛋白的初步观察     

黄萌萌  刘冉  陈平  朱金鲁  卫东  谢芳  李刚  刘思国  张跃灵 《中国预防兽医学报》2020,(2):105-113

为构建猪链球菌(Streptococcus suis)蛋白表面展示系统,本研究通过序列分析,确定猪链球菌的LPxTG蛋白及其信号肽(SP)和胞壁锚定基序(CWA),通过PCR扩增Peno-SP、GFP、CWA的DNA片段并融合,构建强启动子Peno控制表达编码SP-GFP-CWA融合蛋白的DNA片段,将该重组DNA片段连接pSET2载体,获得蛋白表面展示质粒,转化猪链球菌,构建得到以GFP为报告蛋白的猪链球菌蛋白表面展示系统。结果显示,利用猪链球菌的10个LPxTG蛋白及其SP和CWA序列,构建了10个含有Peno-SP-GFP-CWA融合片段的重组pSET2表面蛋白展示质粒pSsPSD1至pSsPSD10,分别转化猪链球菌05ZYH33,PCR鉴定显示其中7个转化猪链球菌。采用western blot初步检测其展示蛋白,结果显示,7个转化阳性菌株均能有效表达GFP蛋白,以成熟GFP条带为指标,均表现出了一定的外源GFP表面展示水平,分别命名为SsPSD1、SsPSD2、SsPSD4、SsPSD7-SsPSD10,其中SsPSD1、SsPSD4、SsPSD8和SsPSD9表面展示水平相对较好,在猪链球菌表面展示外源蛋白方面具有很好的潜力。本研究首次尝试建立猪链球菌蛋白表面展示系统,为猪链球菌表面递呈外源蛋白或抗原提供了新的策略。  相似文献