浅析家禽几种局部大肠杆菌性感染

1概念 大肠杆菌病是指部分或全部由禽致病性大肠杆菌所引起的局部或全身性感染的疾病,包括大肠杆菌陛败血症、大肠杆菌性肉芽肿、气囊病(慢性呼吸道疾病,CRD)、大肠杆菌性蜂窝织炎、大肠杆菌性输卵管炎、大肠杆菌性骨髓炎/滑膜炎、大肠杆菌性全眼球炎及大肠杆菌性脐炎,卵黄囊感染.     

鸵鸟常见疾病综述(二)

3细菌型传染病3.1大肠杆菌病大肠杆菌普遍存在于自然环境和动物肠道中,大肠杆菌病是由埃希氏大肠杆菌引起的一系列临床症状的总称。临床表现有大肠杆菌性败血病、腹膜炎、输卵管炎、滑膜炎、脐带炎、卵黄炎、腹水症等。鸵鸟大肠杆菌病是非洲鸵鸟的一种常见病。     

仔猪水肿病的中兽医治疗

正仔猪水肿病又称猪大肠杆菌性病毒血症,大肠杆菌抗原主要分为三种,分别为H抗原、O抗原和K抗原。大肠杆菌的血清型种类很多,但可致病性大肠杆菌血清型不多。产肠毒素大肠杆菌(ETEC)会导致人和幼畜腹泻。大肠杆菌大多数是没有致病性的,但一定条件下可导致大肠杆菌病(Colibacilosis)。少数大肠杆菌与人和动物的大肠杆菌密切相关,把它们称为病原性大肠杆菌。该病全国各地都有发生,多为散发,传染性不强。仔猪、保育猪、育肥猪和种猪均易发生本     

大肠杆菌噬菌体治疗制剂的研究进展

近年来,由于兽医临床耐药大肠杆菌的不断出现,新抗生素的研制困难重重;因此研究大肠杆菌噬菌体用于治疗大肠杆菌感染受到重视。文章从噬菌体类型、大肠杆菌噬菌体溶菌机制、大肠杆菌噬菌体生物学特性、动物试验等方面进行了论述,旨在为治疗由大肠杆菌引起的疾病提供新的、有效的方法。     

一例种禽大肠杆菌病的治疗

正大肠杆菌病是指部分或全部有禽致病性大肠杆菌所引起的局部或全身性感染的疾病。大肠杆菌病的病原是埃希氏大肠杆菌,而其他传染性病原和非传染性因素常诱发此病的发生。根据感染后的解剖情况可以分为大肠杆菌性败血症、大肠杆菌性腹膜炎、大肠杆菌性输卵管炎等十几种典型的疾病症状。由于大肠杆菌血清型较多,临床表现复杂多样,又多并发或是继发于其他     

肠外致病性大肠杆菌LuxR家族转录调节蛋白YjjQ研究进展

致病性大肠杆菌包括肠道内致病性大肠杆菌及肠外致病性大肠杆菌,肠外致病性大肠杆菌包括:尿道致病性大肠杆菌(Uropathogenic Escherichia coli, UPEC)、新生儿脑膜炎大肠杆菌(Neonatal meningitis Escherichia coli, NMEC),禽致病性大肠杆菌(Avian Pathogenic Escherichia coli, APEC)等“。肠外致病性大肠杆菌常引发腹泻、尿路感染、新生儿脑膜炎和败血症等多种疾病,给人和动物的健康和公共卫生带来严重威胁[1].     

鸡病防治技术（十二）

十二、鸡大肠杆菌病的防治 鸡大肠杆菌病是由埃希氏大肠杆菌引起的一种常见病,其特征是引起心包炎、肝周炎、气囊炎、腹膜炎、输卵管炎、滑膜炎、大肠杆菌性肉芽肿和脐炎等病变。 (一) 病原 埃希氏大肠杆菌。     

猪大肠杆菌病的临床诊断和防治

大肠杆菌病是病原性大肠杆菌引起的不同种动物不同疫病或者病型的统称。包括动物的局部性或者全身性大肠杆菌群、大肠杆菌性腹泻、败血症和毒血症等。猪的大肠杆菌病是病原性大肠杆菌引起的仔猪肠道性疾病,常见有仔猪黄痢、仔猪白痢和仔猪水肿病。临诊以肠炎、肠毒血症为特征。     

一起鸡大肠杆菌性关节炎的诊断报告

鸡大肠杆菌病是由禽致病性大肠杆菌引起的局部或全身性感染的细菌性疾病,包括大肠杆菌性蜂窝织炎、大肠杆菌性腹膜炎、气囊炎、大肠杆菌性关节炎、大肠杆菌性输卵管炎等。大多数禽类对大肠杆菌病易感,其中以幼禽和胚胎最为易感且危害较严重。病鸡、携带者和啮齿类动物的粪便是主要的传染源,通过粪便排出的病原菌,散布于外界环     

鸡大肠杆菌病的鉴别诊断

1鸡大肠杆菌病概述 鸡大肠杆菌病是由埃希氏大肠杆菌的各种血清型菌株引起疾病的总称。大肠杆菌病在临床上有多种症状,如大肠杆菌性败血症、肉芽肿、腹膜炎、输卵管炎、脐炎、滑膜炎、气囊炎、全眼球眼炎、卵黄性腹膜炎等症状。     

鸡病原性大肠杆菌（血清型O78）纤毛亚单位苗免疫原性的研究

本实验利用透射电镜观察了鸡源大肠杆菌（血清型Ｏ７８）表达的纤毛。提取并初步纯化了纤毛。通过ＳＤＳ－聚丙烯酰胺凝胶电泳检测了提取物的纯度及其亚单位分子量。表明提取物属Ｉ型纤毛。用提取纤毛制备油佐剂苗。评估了该苗的免疫原性，免疫组和阳性对照组病级数在极显左异（Ｐ＜０．０１），苗的保护指数分别为一次免疫６４．２８％，两次免疫７４．６０％。用ＥＬＩＳＡ检测了免疫后６８天鸡的抗体消长。通过统计分析二免后抗体     

Comprehensive network map of transcriptional activation of chicken type I IFNs and IFN-stimulated genes

Chicken type I interferons (type I IFNs) are key antiviral players of the chicken immune system and mediate the first line of defense against viral pathogens infecting the avian species. Recognition of viral pathogens by specific pattern recognition receptors (PRRs) induce chicken type I IFNs expression followed by their subsequent interaction to IFN receptors and induction of a variety of IFN stimulated antiviral proteins. These antiviral effectors establish the antiviral state in neighboring cells and thus protect the host from infection. Three subtypes of chicken type I IFNs; chIFN-α, chIFN-β, and a recently discovered chIFN-κ have been identified and characterized in chicken. Chicken type I IFNs are activated by various host cell pathways and constitute a major antiviral innate defense in chicken. This review will help to understand the chicken type 1 IFNs, host cellular pathways that are involved in activation of chicken type I IFNs and IFN stimulated antiviral effectors along with the gaps in knowledge which will be important for future investigation. These findings will help us to comprehend the role of chicken type I IFNs and to develop different strategies for controlling viral infection in poultry.     

Expression of pili and capsule by the avian strain P-1059 of Pasteurella multocida

The avian strain P-1059 of Pasteurella multocida was grown on blood agar (BA), on dextrose-starch agar (DSA), or in Heddleston's hydrogen sulfide test broth. Cells were examined for the presence of pili using electron microscopy after staining with phosphotungstic acid, and they were examined for capsule after ruthenium red staining. Pili were found on the capsulated iridescent type, P-1059I, and on two non-capsulated variants, the blue, P-1059B, and the gray, P-1059G. Many cells grown on BA were heavily piliated. In contrast, fewer cells grown on DSA had pili, and piliation was only slight to moderate. The P-1059I, P-1059B, and P-1059G produced pellicles when grown on broth medium. Pili were found on the circumference of the cells grown on either agar or broth medium. Occasionally a pilus connecting two cells was seen on cells cultured in broth. Cultivation of the P-1059I on DSA containing the iron-chelating agent alpha,alpha'-bipyridyl produced a non-capsulated blue variant. The non-capsulated variant reverted to P-1059I when grown on BA but did not revert when grown on DSA.     

嗜水气单胞菌粘附特性的研究

不同来源的６株嗜水气单胞菌（Ａｅｒｏｍｏｎａｓｈｙｄｒｏｐｈｉｌａ）对１０种不同红细胞的血凝试验表明，Ｊ－１株能凝集所有的１０种红细胞，而与其他菌株的血凝谱有所不同。血凝图式有２种：人、鸡、麻雀的红细胞凝集快，呈大小不等的絮状；而鲫鱼、绵羊、猪、小鼠、兔、鸭、犬的红细胞凝集慢，且呈均匀颗粒状。这两种血凝均能被Ｄ－甘露糖抑制，但不能被Ｊ－１株Ｒ菌毛抑制。组织粘附试验显示，Ｊ－１株能粘附小鼠和鲫鱼的肠组织和肠绒毛。将提纯的Ｒ菌毛预处理肠组织，或用Ｄ－甘露糖或木瓜蛋白酶消化的Ｒ菌毛抗血清Ｆａｂ片段预处理菌体，都不能抑制上述的粘附作用。Ｊ－１株对ＨＥｐ－２细胞显示强粘附，菌体随机粘附在细胞上，有少数侵入细胞浆内。其余５株菌的粘附特性与Ｊ－１株不尽相同。所有６株菌对草鱼肠组织及肠绒毛、ＥＰＣ细胞（鲤鱼乳头状上皮瘤细胞系）均无粘附性。     

Visualization of Surface-specific Antigens in Various Strains of Enterotoxigenic E. coli

Proteinaceous surface antigens of enterotoxigenic E. coli (ETEC) appear as pili, and are important virulence factors as they allow bacteria to attach to the small intestinal mucosa. Surface antigens are classified as colonization factor antigens (CFA) and coli surface antigens (CS). Known groups include CFA/I, CFA/II (consisting of CS1, CS2 and CS3), CA/III and CFA/IV (consisting of CS4, CS5 and CS6). The goal of the present study was to examine the morphology of pili by transmission electron microscopy (TEM) and to localize specific surface antigens by immunolabelling. Using different strains of E. coli grown under various culture conditions, pili were visualized by negative staining and corresponding surface antigens were demonstrated by immunogold-labelling using both polyclonal and monoclonal antibodies. Expression of pili was dependent on culture conditions and sample handling. In contrast to CFA/I and CS3, CS6 pili were not detectable after negative staining. Selected antibodies, however, allowed surface antigens to be demonstrated unequivocally. These results will be of value in investigating the expression of colonizing factors in genetically modified bacterial strains.     

鸡基因组在生物学与农业和医学中的潜在利用

鸡的基因组序列含有大约10亿多碱基对（bp）、20000-23000个基因,这个基因组的很多特性使鸡在生物发生和进化研究中成为了一个理想的生物有机体。鸡基因组的独特结构和鸡基因组序列草图的独特特征为认识脊椎动物进化提供了一个透视的视角,使鸡成为了一个研究生物学的理想生物模型,它们将提高科学对禽类生物学、发育生物学、基础生物科学及医学的认识。运用鸡作为一个全球蛋白质营养源的生物模型和对疾病治疗研究的生物医学模型具有明显的优势,因此,鸡基因组的排序、基因组学工具在生物研究中的利用以及现代选择性育种方案发展的快速进展将会促进鸡基因组在农业和医学中的必然利用。该文将综述鸡基因组的简要独特结构、禽类进化的相关性与在农业与医学中的潜在利用。     

Biological and immunological characterization of pili of Escherichia coli serotypes O1, O2, and O78 pathogenic to poultry

Pili of Escherichia coli serotypes O1, O2, and O78 pathogenic to poultry were isolated and purified by sucrose-density-gradient centrifugation. Each serotype expressed only one type of pilus. The pili of the three serotypes had similar densities and were morphologically similar by electron microscopy. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, however, showed that they were slightly different in subunit molecular mass. Slide agglutination, immunodiffusion, and immunoblot tests were used to test for antigenic relationships between these pili and reference pili. Pili of serotype O78 were type 1, but pili of serotypes O1 and O2 were not, as once believed. However, pili of serotype O2 reacted positively with anti-type 1 serum in immunoblot assay, suggesting the presence of some common antigenic epitopes among these pili.     

Virulence properties of Escherichia coli isolated from ostriches with respiratory disease

Eight Escherichia coli isolates from ostriches with respiratory disease were investigated for the presence of genes encoding the following adhesins: type 1 pili (fim), pili associated with pyelonephritis (pap), S fimbriae (sfa), afimbrial adhesin (afaI), temperature regulated adhesin, curli (crl, csgA) and temperature-sensitive hemagglutinin (tsh). Genes for heat labile (LT) and heat stable (STa and STb) enterotoxins, Shiga toxins (stx1 and stx2), cytotoxic necrotizing factor 1 (cnf), alpha-haemolysin (hly) and aerobactin (aer) production were also investigated. Other characteristics investigated were the presence of hemagglutination activity, growth on an iron-deficient medium, aerobactin production, serum resistance, adherence to chicken tracheal cells, pathogenicity for day-old chicks, and serogroup. Serogrouping showed that four isolates belonged to serogroup O2, two to serogroup O78, one to serogroup O9, and one to serogroup O21. The virulence genes found were: fim in all eight isolates, csgA in seven, aer in six, and pap, crl and tsh in one isolate each. All isolates analyzed were positive for mannose-resistant hemagglutination, adhered in vitro to ciliated tracheal epithelium, grew on iron-deficient medium, and showed serum resistance. Pathogenicity tests on day-old chickens revealed one highly pathogenic isolate, three of low pathogenicity and four isolates with intermediate pathogenicity.     

Relationship of complement resistance and selected virulence factors in pathogenic avian Escherichia coli.

Complement resistance, antibiotic resistance profiles, and virulence profiles of 80 Escherichia coli isolates from the intestines of normal chickens (40 isolates) and chickens diagnosed as having colisepticemia (40 isolates) were compared. Differences were observed between the two groups for antibiotic resistance, siderophore production, presence of type 1 pili, complement resistance, motility, and size of plasmids. The systemic isolates were more likely to have siderophores and type 1 pili, and to be complement-resistant and motile than were the intestinal isolates. No differences between the two groups were observed for colicin production. Further comparison of the 10 most complement-resistant isolates from the systemic group and 10 most complement-sensitive isolates from the intestinal group revealed a correlation between an isolate's resistance to complement and its ability to kill embryos, express type 1 pili, and be motile. Virulence of avian E. coli strains appears to be correlated with complement resistance and the interaction of this resistance with the ability to produce type 1 pili and be motile.     

Attachment of Corynebacterium renale to tissue culture cells by the pili.

One or more cells of Corynebacterium renale strains (serologic types, I, II and III), which possessed numerous pili, frequently were attached to BHK-21 cells, primary dog kidney cells, and primary rabbit kidney cells. The percentage of the cultured cells to which C renal cells were attached was about 70%. The percentage was less with cells of C renale possessing fewer pili, around 30%. After C renale was treated with the homologous anti-pili serum, the percentage of BHK-21 cells to which bacterial cells were attached was even less (22%). In electron micrographs, the pili of C renale were observed to attach themselves to the membranes of BHK-21 cells. The adhesive property of the pili of C renale to tissue culture cells was thus demonstrated.