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1.
为了解山东省肉鸡场禽腺病毒的感染流行特点,为其科学防治提供依据,通过临床症状观察、病毒分离鉴定、鸡胚致病性试验、血凝试验、PCR检测及克隆测序等方法进行病原检测分析。结果表明,发病肉鸡主要表现为精神沉郁、采食减少等临床症状。鸡胚致病性试验可见死亡胚体呈全身出血、体型小、肝肿大现象。血凝试验显示,分离株不具凝集鸡、鸭、大鼠红细胞的特性。对hexon基因进行克隆测序分析显示,LY9株与Ⅰ群禽腺病毒血清8型亲缘性近,与参考株(58株)的核苷酸同源性为98.8%,氨基酸同源性为98.6%。其余8株分离株间的核苷酸同源性为91.3%~99.8%,氨基酸同源性为97.8%~100%;与Ⅰ群禽腺病毒血清4型参考株(HB1510株)属同一进化分支,核苷酸同源性为93.1%~100%,氨基酸同源性为98.9%~100%。结论:从山东省4家肉鸡场分离到的9株病毒均为Ⅰ群禽腺病毒。  相似文献   

2.
【目的】 获得鸡滑液囊支原体(Mycoplasma synoviae,MS)贵州流行株,以进一步开展其病原学及免疫学相关研究。【方法】 从贵州省织金县某肉鸡场共采集107份疑似MS感染病鸡的咽拭子、肿胀关节和脚垫、肿胀组织渗出物进行PCR检测,对PCR筛选的阳性组织样本进行MS分离培养,并进行瑞氏染色、生化试验及VlhA基因序列分析。【结果】 PCR检测筛选到20份阳性样本,从关节和爪垫阳性样本中分离到1株疑似MS,分离株在平板上生长出"煎蛋状"菌落;瑞氏染色可见蓝色细小的球形菌;生化试验中,分离株分解葡萄糖和麦芽糖,但不分解精氨酸、尿素等,与MS标准株生化结果一致;分离培养物经PCR扩增得到821 bp的目的片段;分离株VlhA基因核苷酸相似性分析表明该分离株为MS,与GenBank登录的国内其他地区流行株相似性有地域差异。与安徽、重庆、福建、广东、广西、湖北、湖南、江苏和云南等地区流行株相似性在90.3%~99.7%之间;该分离株与湖南MS流行株相似性最高,达到99.7%;但与国外参考流行株的相似性低;VlhA基因遗传进化树分析显示,该分离株与国内参考株亲缘关系较近,与国外参考株亲缘关系较远。【结论】 本研究成功从引起关节和足垫肿胀的鸡中分离鉴定了1株MS贵州流行株,该分离株存在一定变异,为贵州省MS的分子生物特征及本病的诊断和防控研究提供了基础依据。  相似文献   

3.
本试验通过鸡胚矮小试验、血凝试验和RT-PCR等方法,从华北地区某鸡场发生疑似肾型传染性支气管炎的发病鸡群分离了1株鸡传染性支气管炎病毒,命名为SX01株.结果显示该分离株能引起鸡胚典型的临床症状;经1%胰酶处理后的尿囊液可凝集鸡红细胞,而未处理的则无血凝活性;利用RT-PCR对分离株M基因序列测定分析结果显示,SX01株的M基因核苷酸序列与GX-GL分离株同源性高达99.4%,与QX基因型毒株SDZB0808核苷酸同源性高达99.1%,与H120株同源性仅为90.0%,与BJ/00/02株M基因核苷酸同源性较低,为90.6%.遗传进化分析结果显示,该分离株与中国地方型分离株(GX-GL、SDZB0808、CK/CH/LJL/110302、DY07、IBVSX7)亲缘关系较近,位于同一进化分支;与H120代表的Mass型疫苗株的亲缘关系较远,是一株肾型传染性支气管炎病毒毒株.  相似文献   

4.
为了解陕西省部分地区猪流行性腹泻病毒(PEDV)的遗传和变异情况,采集陕西省部分地区规模化猪场的5份疑似PEDV感染的猪小肠内容物,进行PEDV S、M和N基因的RT-PCR扩增,并对扩增产物进行序列测定和遗传变异分析。结果表明,5份病料均能扩增出PEDV S、M和N基因,5株病毒分别命名为SXSL、SX-BJ、SX-YL、SX-WN和SX-HZ株。序列分析表明,5株毒株之间的S、M和N基因核苷酸序列的同源性分别为96.7%~99.8%、98.4%~100%和97.2%~99.9%;氨基酸序列的同源性分别为97.4%~99.9%、98.2%~100%和98.2%~100%。该5株病毒与中国疫苗株CV777的S、M和N基因核苷酸序列的同源性分别为93.9%~99.8%、98.1%~100%和95.3%~99.9%,氨基酸序列的同源性为93.6%~99.9%、96.2%~100%和98.2%~100%。遗传进化分析结果显示,5个陕西分离株的S基因与中国疫苗株CV777亲缘关系较远,与近年来中国株、日本株以及韩国株亲缘关系较近。SX-SL株、SX-BJ株和SX-YL株的M和N基因与中国疫苗株CV777亲缘关系较近,且与中国株CHGD-01亲缘关系密切。SX-WN株和SX-HZ株的M和N基因与中国疫苗株CV777亲缘关系较远。该5株病毒的S基因以及SX-WN株和SX-HZ株的M基因和N基因变异程度较大,而SX-SL株、SX-BJ株和SX-YL株三个流行株均与中国株CHGD-01亲缘关系密切,并且与近年在陕西省流行的PEDV也不完全相同。  相似文献   

5.
经鸡胚绒毛尿囊膜(CAM)接种、易感鸡接种试验、电镜观察,从安徽地区疑似病鸡的法氏囊组织分离到3株传染性法氏囊病毒。分离株人工感染4周龄鸡,致死率分别为92%、83%、67%。接种9~10SPF鸡胚测得的鸡胚半数致死量(ELD50)分别为10-6.8/0.2mL、10-5.4/0.2mL、10-4.6/0.2mL。应用Nested-PCR分别对3株分离株VP2基因高变区进行克隆测序和序列分析,结果表明:3个分离株与国内外参考超强毒株的核苷酸同源性为97.2%~99.5%,氨基酸同源性为99.3%~100%,VP2高变区核苷酸和推导的氨基酸符合传染性法氏囊病病毒超强毒株特征。  相似文献   

6.
【目的】了解中国冀南地区滑液支原体(Mycoplasma synoviae,MS)的流行和耐药情况,为该地区防控MS感染提供科学依据。【方法】于2019—2022年采集冀南地区疑似MS感染的7个规模化鸡场样品(发病鸡的气囊、腭裂或爪垫渗出液)进行病原分离培养及PCR鉴定,对分离株进行vlhA基因分型序列分析,采用微量肉汤稀释法测定分离株最小抑菌浓度(MIC)。【结果】所采集样品中分离出9株疑似MS菌株,均可使液体培养基颜色变为橘黄,在固体培养基中菌落形态为典型的“煎荷包蛋”样;PCR鉴定及测序结果显示,9株分离株与MS HN01株相似性为100%,表明分离株均为MS;vlhA基因分型序列结果显示,9株MS富含脯氨酸重复序列(PRR)区均为35个氨基酸,属于L型,核苷酸序列相似性为99.7%~100%,与中国其他地区L型菌株亲缘关系较近,与泰国L型菌株亲缘关系较远;MIC测定结果显示,9株MS对泰乐菌素、替米考星、螺旋霉素、林可霉素、沃尼妙林、泰妙菌素、多西环素、土霉素、氟苯尼考、恩诺沙星的MIC50/90值分别为0.25/0.25、0.5/0.5、0.5/0.5、...  相似文献   

7.
从广东珠三角地区某鸽场的发病鸽群采样,接种10日龄SPF鸡胚后分离到一株病毒,命名为JP株。系列微量血凝和微量血凝抑制试验结果表明,新城疫病毒(NDV)阳性。测序结果显示,该NDV分离株F蛋白裂解位点的氨基酸序列为112 R-R-Q-K-R-F117,具有强毒株序列特点;F基因分型表明,JP株属于基因Ⅵ型。Blast结果显示,JP株F、HN基因序列均与基因Ⅵ型pi/CH/LGD/110208株同源性最高,均达99%。同源性比较发现,F和HN基因、蛋白都与基因Ⅵ型新城疫毒株同源性较高,分别为92.5%~99%、95.5%~99.1%和90.6%~98.7%、91.9%~99%,而与国内常用疫苗株B1、La Sota、Mukteswar等同源性较低,分别为83.2%~85.9%、89.2%~91%和79.3%~83.4%、86%~89.5%。分离的JP株属于基因Ⅵ型,并与国内常用疫苗株存在一定的差异。  相似文献   

8.
《畜牧与兽医》2016,(3):32-36
从福建某鸡场发病鸡的气管和肾脏组织中分离到1株病毒,通过病毒对SPF鸡胚的致病性特征、血凝特性、电镜观察及RT-PCR鉴定等方面的研究,证实该病毒为鸡传染性支气管炎病毒(IBV),并命名为GZ毒株。通过RT-PCR对该毒株的3CLpro基因片段进行扩增,随后进行克隆与测序。该序列与参考毒株的核苷酸序列分析显示,GZ株的3CLpro基因片段与参考毒株的同源性为85.9%~98.5%,与Beaudette毒株核苷酸序列同源性最高(98.5%),而与H120株同源性为89.7%,与LX4株同源性最低(85.9%)。遗传演化分析显示,GZ分离株与参考株可以划分为3个群,GZ分离株与Beaudette毒株处于同一分支,而与LX4、BJ及Massachusetts毒株亲缘关系较远。  相似文献   

9.
为了分析河南许昌地区规模化肉鸡场滑液囊支原体流行情况及耐药情况,本试验从许昌地区规模化肉鸡场采集疑似鸡滑液囊支原体感染的病料组织179份,采用细菌分离培养、形态观察及PCR等方法进行滑液囊支原体鉴定,采用K-B药敏纸片法对分离的滑液囊支原体进行耐药性检测。结果显示,分离得到87株鸡滑液囊支原体,其对金霉素、土霉素、吉他霉素、替米考星、多西环素、泰乐菌素和林可霉素耐药率分别为98.8%、94.3%、90.7%、78.2%、61.5%、58.8%和57.7%,对其他抗菌药的耐药率介于10.3%~17.9%;分离菌株呈现多重耐药性,以耐8、7、6种抗菌药分离菌株最多,分别占分离菌株的16.1%、17.2%和19.5%。结果表明许昌地区规模化肉鸡场滑液囊支原体流行严重,对临床中常用药物出现严重耐药性。本试验结果可为该地区的规模化肉鸡场滑液囊支原体防控提供指导。  相似文献   

10.
采用常规流行病学调查方法,对枣庄市6个地区13个肉鸡群和13个蛋鸡群的ND进行了流行病学调查,结果发现,13个疑似ND肉鸡群的发病日龄一般在7~49日龄之间,发病率和死亡率分别为35%~90%和35%~68%;13个蛋鸡群的发病日龄在70~480日龄之间,发病率、死亡率和产蛋下降率分别在10%~60%、3%~18.7%和10%~50%之间;不同品种的鸡均可发生;肉鸡以冬季多发,蛋鸡以春、秋季多发。通过SPF鸡胚接种和血凝试验(HA)、血凝抑制试验(HI),从26个疑似鸡ND的病鸡群中分离到了20株NDV,其中12株为强毒株,5株为中等毒株,3株弱毒株。用分离的NDV株感染30日龄非免疫鸡,发现发病率为100%,病死率在75%~100%之间,临床症状、病理变化与自然发病鸡相同。通过流行病学调查,初步探明了枣庄地区鸡场发生ND的原因。  相似文献   

11.
旨在了解滑液囊支原体(Mycoplasma synoviae,MS)遗传多样性,本研究对7株MS四川分离株进行全基因组测序及生物信息学分析.采用Illumina HiSeq平台和PE文库结合方式全基因组测序,运用各数据库注释,用MEGAX软件将7株MS与NCBI收录的8株MS全基因比较.结果 显示,分离自同一鸡场的4株...  相似文献   

12.
为了解凉山州腹泻仔猪猪圆环病毒2型(PCV2)的感染情况,采用PCR方法对采自四川省凉山州西昌市和喜德县7个猪场85份腹泻仔猪粪便、病变组织等样品进行PCV2检测,并将扩增到的PCV2 ORF2基因片段进行测序和序列分析。结果显示,PCV2阳性样品有22份,阳性率为25.9%,阳性猪场占71.4%(5/7)。22个ORF2基因片段长度均为459 bp,核苷酸同源性为92.8%~100%,氨基酸同源性为93.5%~100%。构建的系统进化树显示22个测序序列分别处于2个分支:PCV2b和PCV2d,但未形成明显的地理分支。结果表明凉山州猪群中PCV2感染较为普遍,且以PCV2d亚型为主,并存在一定程度的遗传变异。  相似文献   

13.
山羊支原体性肺炎流行病学调查   总被引:2,自引:1,他引:1  
山羊支原体性肺炎是威胁山羊养殖的重要传染病,为了解其流行情况,对四川省主要山羊养殖地区的山羊支原体性肺炎进行了流行病学调查。从四川省7个地区山羊养殖场采集肺脏和鼻腔棉拭子样本共135份,经过分离鉴定得到42株支原体,其中绵羊肺炎支原体36株,丝状支原体6株;其中6个羊场仅分离到绵羊肺炎支原体,1个羊场同时分离到绵羊肺炎支原体和丝状支原体。本试验结果表明,绵羊肺炎支原体是引起四川省山羊支原体性肺炎的主要病原,个别地方存在绵羊肺炎支原体和丝状支原体混合感染。  相似文献   

14.
2009年我国部分地区禽白血病分子流行病学调查   总被引:12,自引:3,他引:9  
为了解自2009年年初以来国内一些地区禽白血病流行情况及流行毒株的分子特征,我们从湖北、黑龙江、山东、辽宁、吉林、广东、宁夏、安徽8个省区39个鸡场采集疑似禽白血病病料样品178份,用ALV-A、ALV-B和ALV-J特异性引物,通过PCR方法进行检测。结果表明,8个省的35个鸡场的124份病料中检出了ALV-J(69.7%);25份病料中检出了ALV-A(13.9%);7份病料中检出了ALV-B(3.9%)。14个分离毒株env基因氨基酸同源性为84.3%~99%;与J亚群原型毒株HPRS-103的氨基酸序列同源性为87.3%~98.2%;与其它J亚群env基因氨基酸序列同源性为83%~97.4%。遗传进化分析表明,14个ALV-J分离株分别分属于不同的分支。其中,LJL09DH02分离株与其它分离株及参考毒株的的亲缘关系最远,与HPRS-103的氨基酸同源性仅为87.3%。另外4个分离株的env基因与HPRS-103的氨基酸同源性低于93%,其余9株与HPRS-103的同源性较高(96.6%以上)。该调查结果表明,我国目前ALV的感染主要以J亚群为主,ALV-A和B同时存在。  相似文献   

15.
Mastitis caused by Staphylococcus aureus is a disease of major economic importance to the dairy industry. Transmission occurs during milking, with chronically-infected cows acting as the major reservoirs of infection. PCR-coagulase gene typing of 151 S. aureus isolates from seven farms generated only six PCR types, with 110 (73%) isolates assigned to PCR type 1 and 23 (15.2%) isolates assigned to type 2. PCR type 1 was the predominant type on five of the seven farms, including farms in geographically separated regions of Victoria, while type 2 predominated on two farms. With the exception of the 41 isolates from one farm, all isolates were resistant to penicillin, but susceptible to other antibiotics that are routinely used to manage mastitis in dairy cattle. Nine of 11 cows with chronic S. aureus infection showed evidence of persistence of a single PCR type for periods of up to 9 months. Two different PCR types of S. aureus were isolated from the other two cows over the same period.  相似文献   

16.
Ornithobacteriosis is an infectious disease of avian species that has been reported in almost all countries around the world, except Thailand. The objectives of this study were to determine the seroprevalence of Ornithobacterium rhinotracheale (ORT) and to isolate and identify ORT in broilers and broiler breeders in Thailand. Chicken antibodies had been randomly checked from 17 farms (19 flocks) of broilers and 23 farms (28 flocks) of broiler breeders. The seropositive flocks were 63% and 100% in broilers and broiler breeders, respectively. The sera analysis showed that the individual 280 broiler sera antibody responses were 67.5% negative, 12.9% suspect, and 19.6% positive. The individual antibody responses of 510 broiler breeder sera revealed 12.2% negative, 38.0% suspect, and 49.8% positive samples. The bacteria were isolated and identified by polymerase chain reaction (PCR). Bacterial isolation and identification revealed that nine isolates of the 12 PCR analysis samples showed positive results to PCR analysis. All the positive PCR samples were collected from the broiler breeder farms.  相似文献   

17.
Screening of broiler flocks for their Campylobacter carriage on farm level and consequently the spread of Campylobacter spp. during slaughtering can help to identify hygiene control points. Therefore, between December 2001 and August 2002 in total 51 broiler flocks from three farms of different geographical regions in Germany were analysed for thermophilic Campylobacter. Campylobacter spp. were isolated from 45% of the broiler flocks examined. Subsequently, 1101 samples were taken from 22 flocks during different stages of processing. Samples were collected from: transport crates before and after cleaning/disinfection, evisceration, post-scalded and post-chilled carcasses and endproducts. Additionally, 45 selected Campylobacter isolates of droppings were genotyped by pulsed-field gel electrophoresis (PFGE). Campylobacter carriage of flocks showed seasonal variation, with the highest contamination rate during the period of June to August. No evidence was found for a horizontal transmission from one broiler flock to the next via a persistent house-contamination. In each positive flock, one to three different genotypes were found. One or two clones dominated isolations obtained from the farm level. The fact that in different flocks indistinguishable isolates of clonal origin were detected during the same rearing period suggested a transmission between the broiler flocks or an intermittent common external source. In one case, isolates of clonal origin were detected in various farms during different rearing periods. Sampling during processing confirmed that the entrance of a positive flock resulted in contamination of the abattoir environment. Campylobacter spp. were isolated from all sampling stages along the processing line, with a percentage of 91.1-100 of isolates at different stages of slaughtering.  相似文献   

18.
During an epidemiologic study of poultry colisepticemia on 2 Saudi Arabian poultry broiler farms, Escherichia coli was isolated from 101 (40.4%) of the 250 specimens examined. The antigenic structure and the drug resistance pattern of 65.4% of the E coli isolates from different sources were used as epidemiologic markers to trace the source of the infection. The predominant E coli serotypes involved in infections of 2 poultry broiler progeny farms were 033:H4 (51.8%) and 078:H- (19.6%) that had the following respective drug resistance patterns: furazolidone-streptomycin-sulfathiazole and streptomycin-sulfathiazole-tetracycline. Escherichia coli strains with typical epidemiologic markers were isolated from various sources on a broiler breeding farm, but not from well waters of the infected progeny farm. Three other E coli serotypes (045:H10[14.3%], 0119:H27[1.8%], and 0145:H25[1.8%]) were involved in poultry infection, but to a lesser extent. These 3 serotypes were multiply resistant against 5 to 6 of the antimicrobials evaluated.  相似文献   

19.
为揭示冰鲜鸡生产链中沙门氏菌的分布及传播机制,本研究于2013年7月~2013年12月采集广东某大型一体化养鸡企业下属2个种鸡场、2个孵化场、2个肉鸡场、1个屠宰场和5个销售点样品,用常规法和PCR进行沙门氏菌的分离鉴定,并对分离出的沙门氏菌进行血清学鉴定和PFGE分子分型.种鸡场、肉鸡场、屠宰场和销售点的沙门氏菌的检出率分别为1.46%(7/480)、7.00%(21/300)、62.86%(22/35)和54.67%(41/75),孵化场雏鸡胎粪检出率为1.11%(2/180),死胚检出率为12.00%(9/75).屠宰和销售环节是沙门氏菌污染的重要环节,食品安全风险较高.102株沙门氏菌共产生24种不同的PFGE谱型,从不同环节分离到多组相似度为100%的沙门氏菌,表明冰鲜鸡生产链中存在沙门氏菌沿生产链传播的现象.  相似文献   

20.
Multilocus enzyme electrophoresis (MLEE) was used to identify, examine genetic relationships and look at disease associations of a collection of 53 intestinal spirochaete isolates previously recovered from the faeces of adult hens on 14 farms in Qld, Australia. The MLEE results were compared with those previously obtained using species-specific PCR amplifications. The isolates were divided into five Brachyspira species groups by MLEE: Brachyspira murdochii (n=17), B. intermedia (n=15), B. pilosicoli (n=14), B. innocens (n=2) and "B. pulli" (n=1). Three new MLEE groups each containing single isolates also were identified. The results of the PCR assay for B. pilosicoli were concordant with the MLEE results, but the 23S rDNA-based PCR for B. intermedia had failed to detect 8 of the 15 isolates. The B. innocens/B. murdochii nox-based PCR had correctly identified all the isolates of B. murdochii, but did not identify either of the two B. innocens isolates. Using MLEE, isolates from two farms (14%) were identified as B. murdochii, whilst the pathogenic species B. intermedia and B. pilosicoli were present in hens from eight (57%) and five (36%) farms, respectively, and were identified together in four (29%) farms. All seven of the farms with production problems or wet litter were colonised with B. intermedia and/or B. pilosicoli. Six farms had multiple spirochaete isolates available for examination. Two broiler breeder farms both had five isolates of B. pilosicoli that shared the same MLEE electrophoretic type (ET), whilst one laying hen farm had three isolates of B. intermedia that all belonged to the same ET. Hence on each of these farms a predominant strain of a pathogenic species was present. On the other farms isolates of the same species were more diverse and belonged to different ETs. These results show that the epidemiology of intestinal spirochaetal infections in broiler breeder and laying hen flocks can vary considerably between farms, although the reasons for these differences were not established.  相似文献   

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