海安县鸡大肠杆菌病病原的分离鉴定及多价灭活苗的研制

为了确定海安县鸡大肠杆菌病的病原并研制多价灭活苗,试验对从海安县兽医站门诊及12个大型养殖场具有疑似大肠杆菌病病变的252只病死鸡进行了病原分离及鉴定。结果表明:共分离、鉴定出大肠杆菌226株,定型198株;共测出23个血清型,其中O78(32株)、O18(26株)、O2(21株)、O88(17株)、O1(13株)、O11(10株)6种血清型占定型菌株的60.1%,为海安县大肠杆菌优势血清型;将此6种优势血清型大肠杆菌制成多价灭活苗免疫雏鸡,安全性好,保护率高。     

河南省鸡源致病性大肠杆菌的分离鉴定

从河南省32个县市的典型大肠杆菌病病变的病、死鸡中,分离到致病性大肠杆菌93株,分别对各菌株进行致病性试验、生化鉴定和血清型鉴定。结果表明:本省致病性大肠杆菌的优势血清型为O78、O1、O2,分别占定型菌株的35.14%、18.92%、13.51%,菌株生化鉴定的结果与其致病力强弱和血清型无一定的相关性。     

青岛地区肉鸡致病性大肠杆菌血清型鉴定及药敏试验

本试验对采自青岛地区多个肉鸡场的疑似大肠杆菌病的病、死鸡内脏器官进行病原的分离鉴定,并对大肠杆菌分离株进行培养特性、血清型及耐药性的检测.共分离到25株大肠杆菌,鉴定出15株血清型,其中以O1、O22 、O157、O24血清型为主,占定型菌株的60%.其中O22血清型占定型菌株的12%,为优势血清型.细菌的耐药性检测结果显示,分离菌株呈现出不同程度的耐药性,25株大肠杆菌对庆大霉素、阿米卡星高敏比例分别为88%和56%,卡那霉素、硫酸安普霉素次之,敏感菌株比例在20%~48%之间,乳酸环丙沙星等抑菌作用低,敏感菌株比例低于10%.而氟哌酸等对所分离的菌株几乎无抑制作用.     

大连普兰店地区鸡大肠杆菌优势血清型筛选

本试验从普兰店地区部分养鸡场采集具有典型临诊特征的鸡大肠杆菌病的病、死鸡病料,进行细菌分离培养和鉴定,分离到17株鸡大肠杆菌。对此17株大肠杆菌进行血清型鉴定,鉴定出血清型15株,分别属于O18、O15、O8、O78、O35,其中O35血清型共6株,占定型菌株的40%;O18血清型共5株,占定型菌株的33.3%。结果表明O35型和O18型鸡大肠杆菌为普兰店地区优势流行血清型。1病料采集鸡大肠杆菌病主要临诊表现有脐炎型、急性败血型、气囊炎型、全眼球炎型、卵黄性腹膜炎型。败血症型在临床上主要表现为纤维     

云南省鸡致病性大肠杆菌的血清型鉴定及药敏试验

从云南省各地州、市(县)主要养鸡场收集到418份疑似鸡大肠杆菌病的死鸡或濒死鸡病料,分离到280株大肠杆菌。对其进行生化试验、致病性试验、血清型鉴定及药敏试验。结果表明:分离菌株能定型的血清型共计28种,其中O78菌株占34.29%,O11、O88菌株各占8.93%、7.86%,为云南省流行的优势血清型。分离菌株对3日龄雏鸡具有很强的致病性,33.57%(94/280)的菌株为强毒株,39.29%(110/280)的菌株为中等毒力株。多数菌株对头孢曲松、头孢噻呋、丁胺卡那霉素、氟苯尼考等药物敏感,对青霉素、红霉素、新霉素、环丙沙星等产生了较强的耐药性。     

烟台市肉鸡大肠杆菌分离及血清型鉴定

从烟台市规模化肉鸡场疑似病鸡和祖代、父母代肉种鸡场1日龄雏鸡卵黄囊、死亡鸡胚共696例肉鸡样品中,分离鉴定出169株大肠杆菌,总分离率为24.28%,疑似病鸡、死胚、雏鸡卵黄囊的分离率分别为45.7%(143株)、38%(19株)、2.1%(7株);通过平板凝集和微量凝集方法对169株分离菌进行O抗血清定型,137株分离菌分属17个O血清型,定型菌株占全部菌株的81.07%,其中O24、O161、O18、O78、O11、O1血清型数量最多,共96株,占定型菌株的70.07%,占全部分离菌株的56.80%,这6种血清型为烟台市肉鸡大肠杆菌的优势血清型。     

泰安地区鸡源致病性大肠杆菌流行病学调查与耐药性分析

正本调查对鸡场采集的疑似鸡大肠杆菌病例的相关病料进行大肠杆菌的分离鉴定,共分离鉴定出14株鸡源大肠杆菌,以微量平板凝集试验鉴定分离菌株的O抗原血清型,分别属于O78、O2和O1等3个血清型,其中O78(6/14)、O2(6/14)为主要流行血清型,占分离菌株总数的85.71%。选取了20种常用治疗肠杆菌病的抗生素对14株鸡源大肠杆菌分离株进行药敏试验,对14株大肠杆菌     

山西省致病性猪大肠杆菌分离及生物特性研究

研究从山西省主要养猪区80多个养猪场(户)的病死猪及疑似大肠杆菌病猪粪便、肠道、肛门等部位采集病料接种于营养琼脂平板、麦康凯琼脂平板、伊红美蓝培养基等纯化培养,将疑似菌落革兰氏染色、镜检;对初步分离菌经生化试验、致病性试验、大肠杆菌O抗原血清型鉴定等,对山西省流行的猪大肠杆菌病病原进行生物学特性研究。研究结果表明,病原菌纯化、镜检结果有123株疑似菌株符合猪大肠杆菌形态特征;生化试验中有8株病原菌产生H2S,有5株病原菌VP试验、枸橼酸盐利用试验是阳性,这13株病原菌不符合猪大肠杆菌的生化特性,其余110株病原菌符合大肠杆菌生化特性;致病性研究结果表明有97株病原菌是致病性猪大肠杆菌;大肠杆菌O抗原血清型鉴定结果:94株血清型分属于36个血清型,其中O138、O101、O9、O107、O141有35株,共占所鉴定分离菌株的37.2%,这几种血清型均为山西这80多个猪场目前流行的优势血清型,通过鉴定摸清了流行在山西省猪致病性大肠杆菌血清型特点、优势血清型菌株及分布状况。这一研究结果为山西省制定猪大肠杆菌病防治策略提供了依据。     

临沂市鸡源致病性大肠杆菌的优势血清型监测及其致病性试验

为了查清我市禽大肠杆菌的血清型及其致病性,对我市不同区域的23个规模化养鸡场及60个养鸡户的412份疑似大肠杆菌病病例进行了细菌分离,并对其进行了生化试验、致病性试验、血清学鉴定。结果:(1)412份病料中分离出了362株大肠杆菌,分离率为87.9%;⑵不同区域的鸡场流行的血清型有较大差异,在362个分离株中,除了27株未能定型、12株自凝外,共鉴定出323个分离株的O型血清型,占分离株的89.2%,这些定型菌株覆盖了36个血清型;(3)优势血清型为O1、O78、O18、O11、O88、O24,这6种血清型共占定型菌株的56.3%;⑷6种优势血清型均具有致病性,其中O1、O78、O18、O11、O24为高致病性菌株,O88为中致病性菌株。     

保定市鸡源致病性大肠杆菌的流行病学及药敏试验

从保定市不同鸡场疑似大肠杆菌病的病鸡中,分离到致病性大肠杆菌54株,对此54株大肠杆菌进行血清型鉴定,除了6株未能定型外,其余分离株的O血清型共有8个,分别为O1、O2、O5、O18、O78、O26、O76和O88,其中O78、O26、O1为主要血清型,分别占鉴定菌株的39.6%、27.1%和16.7%。用20种临床常用的抗菌药物对分离菌株进行药物敏感性试验,结果表明,分离菌株呈现出不同程度的耐药性,其中氨苄青霉素和四环素的耐药率最高,其次为阿莫西林。大多数为多重联合耐药;而阿米卡星、头孢噻呋和头孢噻吩的敏感率较高,其中以头孢噻呋(94.5%)最敏感。     

Recombinant Iss as a potential vaccine for avian colibacillosis

Avian pathogenic Escherichia coli (APEC) cause colibacillosis, a disease which is responsible for significant losses in poultry. Control of colibacillosis is problematic due to the restricted availability of relevant antimicrobial agents and to the frequent failure of vaccines to protect against the diverse range of APEC serogroups causing disease in birds. Previously, we reported that the increased serum survival gene (iss) is strongly associated with APEC strains, but not with fecal commensal E. coli in birds, making iss and the outer membrane protein it encodes (Iss) candidate targets for colibacillosis control procedures. Preliminary studies in birds showed that their immunization with Iss fusion proteins protected against challenge with two of the more-commonly occurring APEC serogroups (O2 and O78). Here, the potential of an Iss-based vaccine was further examined by assessing its effectiveness against an additional and widely occurring APEC serogroup (O1) and its ability to evoke both a serum and mucosal antibody response in immunized birds. In addition, tissues of selected birds were subjected to histopathologic examination in an effort to better characterize the protective response afforded by immunization with this vaccine. Iss fusion proteins were administered intramuscularly to four groups of 2-wk-old broiler chickens. At 2 wk postimmunization, chickens were challenged with APEC strains of the O1, O2, or O78 serogroups. One week after challenge, chickens were euthanatized, necropsied, any lesions consistent with colibacillosis were scored, and tissues from these birds were taken aseptically. Sera were collected pre-immunization, postimmunization, and post-challenge, and antibody titers to Iss were determined by enzyme-linked immunosorbent assay (ELISA). Also, air sac washings were collected to determine the mucosal antibody response to Iss by ELISA. During the observation period following challenge, 3/12 nonimmunized chickens, 1/12 chickens immunized with 10 microg of GST-Iss, and 1/12 chickens immunized with 50 microg of GST-Iss died when challenged with the O78 strain. No other deaths occurred. Immunized chickens produced a serum and mucosal antibody response to Iss and had significantly lower lesion scores than nonimmunized chickens following challenge, regardless of the challenge strain. This study expands on our previous report of the value of Iss as an immunoprotective antigen and demonstrates that immunization with Iss can provide significant protection of chickens against challenge with three different E. coli strains.     

鸡源大肠埃希氏菌部分生物学特性研究

对从天津地区分离到的71株鸡大肠杆菌的部分生物学特性包括致病性、血清型、耐药特性和免疫原性等进行了研究。结果表明其中60株为致病性菌株,占分离菌株的84.5%;60个致病性菌株共定型出45个菌株,分属O1、O2、O5、O6、O20、O45、O53、O74、O75、O78、O88、O89、O92、O107、O111、O145等16个血清型,其中O78、O88、O2、O45、O53和O145为优势血清型,占定型菌株的73.4%;试验菌株具有广泛的耐药性,60个致病性菌株均为多重耐药。免疫原性测定试验结果表明,O2、O78、O88血清型菌株均可对相同血清型菌株提供很好的保护,但3个血清型菌株之间缺乏有效的保护。     

新疆阿拉尔垦区鸡致病性大肠杆菌的分离与鉴定

从新疆阿拉尔垦区的不同鸡场和屠宰点收集典型病变的病料100份,从中分离出大肠杆菌26株,并进行血清型鉴定,其主要血清型主要有O_(127)、O_(111)、O_(55)、O_(26)、O_(126)、O_(128)、O_(125)、O_(4),动物回归试验显示所分离的6种血清型的菌株对3～5日龄内雏鸡具有很强的致病作用,多数菌株可使接种雏鸡94.4%死亡。通过药敏试验结果表明,所分离26株大肠杆菌对头孢唑林钠最敏感,为该垦区鸡的大肠杆菌病诊断和预防提供技术支持。     

Serotyping of O and pilus antigens of Escherichia coli strains isolated from chickens with coli-septicemia.

One hundred and fifty one Escherichia coli strains were isolated from broiler chickens with coli-septicemia in Aichi (63 strains), Shizuoka (58 strains), and Kagoshima (30 strains) prefectures from 1980 to 1987, and their O and pilus antigens were serologically typed. One hundred and twenty five strains (82.8%) were typed into 23 O serogroups, and twenty six strains (17.2%) remained untypable. The predominant O serogroups were O2 (35 strains, 23.2%) and O78 (24 strains, 15.9%). Distribution of O serogroup was different, depending on prefectures where they are isolated. In total, 109 strains (72.2%) possessed Type 1 and/or Fmsha pili (Type 1; 41 strains, Fmsha; 22 strains, and Type 1 and Fmsha; 46 strains), and 42 strains (27.2%) were non-piliated. All the strains lacked K88, K99, 987P, F41, and Att25 pili. The ratios of piliated strains to non-piliated ones were almost the same among the three prefectures. Strains possessing Type 1 pili showed variety of O antigens, but most of the strains with Fmsha pili belonged to O2 serogroup.     

Virulence factors of avian pathogenic Escherichia coli strains isolated from chickens with colisepticemia in Japan

The virulence factors of avian pathogenic Escherichia coli (APEC) isolated in Japan were investigated. Serogroups O, serotypes K1 and K5, and genes cva C, iss, iutA, papA, tsh, and usp, which have been thought to be related to virulence, were examined for their association with E. coli strains isolated from diseased and healthy chickens. The frequently recognized serogroups O1, O2, and O78 were found in 56 of 125 (44.8%) strains of diseased chickens (APEC) versus 13 of 100 (13.0%) strains of healthy chickens (commensal E. coli), a significant difference at risk ratio < 0.01. Although iss, iutA, and tsh were widely distributed in the APEC irrespective of O serogroup, papA, usp, and the K1 serotype were detected in serogroup O2 of APEC. The kfiD gene related to the K5 capsule and VT, LT, and ST genes related to exotoxins were not detected in any strains examined.     

陕西省鸡胚源性大肠杆菌的分离鉴定

从陕西关中六个种鸡场的１９８只死胚及出壳弱雏中分离出９８株大肠杆菌,平均分离率为４９．５％。通过小鸡致病力试验,筛选出６３株具有致病力的菌株,占分离菌的６４．３％。生化鉴定表明,这些致病菌均符合大肠埃希氏菌的生化特性。血清型鉴定可确定６种,其中以Ｏ１、Ｏ２、Ｏ７８为主,分别占鉴定菌的４４．４％（２８／６３）、３３．３％（２１／６３）和９．５％（６／６３）,另三种为Ｏ２２、Ｏ７５、Ｏ８９共占８．０％（５／６３）。有３株未定型,占４．８％（３／６３）。用１６种抗生素进行药敏试验,对先锋霉素Ｖ和恩诺沙星高度敏感,对羧苄青霉素、氨苄青霉素、氯霉素、卡那霉素、磺胺嘧啶、新霉素、链霉素中度敏感。     

Characterization of Escherichia coli isolated from cases of avian colibacillosis.

Forty-four western Canadian isolates of Escherichia coli associated with colibacillosis of turkeys and chickens were examined for serotype, antibiotic resistance, and production of aerobactin. The isolates belonged to fourteen O serogroups, with 39% of the strains being non-typeable. A high frequency of resistance to tetracycline, kanamycin, neomycin, cephalothin, streptomycin and erythromycin was observed. Most isolates produced aerobactin. Ten E. coli belonging to serogroups O1, O2 and O78 were also examined for pili production, hemagglutination, serum sensitivity, production of iron-regulated outer membrane proteins (IROMPS), and virulence. All isolates examined produced pili, exhibited mannose-sensitive hemagglutination of avian red blood cells and produced IROMPS under iron-restricted growth conditions. The five isolates of serogroup O1 and O2 were resistant to killing by turkey serum and were highly virulent. Only two of the five isolates of serogroup O78 were serum resistant. No correlation between serum resistance and virulence was observed in serogroup O78.     

肉仔鸡病原大肠杆菌地方分离株的血清型鉴定

从河北的三河、滦南、乐亭、卢龙及昌黎等地 2 9个养鸡场 (户 )分离鉴定了 82株病原大肠杆菌 ,用 54种常见动物病原大肠杆菌单价 O抗血清进行了血清型鉴定。结果 82株分离菌有65株被鉴定出了相应 O血清群 (占鉴定菌株的79.2 6%) ,分属 6种不同血清型 ,其中以 O78和O45两种为优势血清型 (占定型菌株的64.61 %) ,其余 4种 O血清群占定型菌株的 3 5.3 9%,尚有 1 7株未能定型 (占鉴定菌株的 2 0 .74%)     

动物性食品源大肠杆菌O血清型鉴定及其K88菌毛基因检测

本研究对河北省冀东地区农贸市场和超市采集的生猪肉、生鸡蛋和生羊肉等分离得到的20株大肠杆菌进行大肠杆菌血清型鉴定;并检测不同血清型大肠杆菌的K88菌毛基因。采用常规方法进行大肠杆菌的O血清型鉴定,用PCR方法检测K88菌毛基因。分离鉴定的20株大肠杆菌有7种血清型,包括O38、O78、O88、O11、O107、O91、O9,其中O38、O78为优势血清型菌,均占分离菌株的25%(5/20)。在分离的动物性食品源大肠杆菌中有30%(6/20)的菌株K88菌毛基因扩增呈阳性。结果表明,O78、O38为冀东地区动物性食品源大肠杆菌常见血清型,30%(6/20)的菌株K88菌毛基因扩增阳性。     

禽致病性大肠杆菌的分离、O血清群鉴定及药物敏感试验

对2005年5月~2016年3月自河北、山东、河南、江苏、陕西、辽宁等省发病鸡场疑似大肠杆菌病的病死鸡病变部位分离的194株禽致病性大肠杆菌进行了生化特性测定、O抗原血清群鉴定及药敏试验。试验用5种大肠杆菌单因子（O1、O2、O57、O65、O78）阳性血清进行O血清群鉴定,确定了124株O血清群,占鉴定菌株数的63.9%（124/194）,其中O1 3株、O2 26株、O57 15株、O65 47株和O78 33株,O65和O78为优势菌株,而O2和O57血清群菌株次之,O1血清群菌株最少。8种药物（氨苄西林、新霉素、多西环素、磺胺间甲氧嘧啶、替米考星、环丙沙星、头孢噻呋和氟苯尼考）的药敏试验结果表明,受试的5株大肠杆菌分离株均对环丙沙星和新霉素敏感,而对其他药物均有不同程度的耐受。本研究结果表明O65、O78、O2和O57血清群高度流行,为进一步研发多价菌苗奠定了基础。