鸡传染性喉气管炎病毒的分离鉴定

采用自然感染鸡的气管粘膜及分泌物为材料，以鸡胚接种分离出一株病毒ＣＬ９４。通过接种鸡胚的病变特点、回归本动物试验、琼脂免疫扩散试验、毒价测定、中和试验以及对有机溶剂的敏感试验等证明ＣＬ９４分离株是鸡传染性喉气管炎病毒（ＩＬＴＶ）。为证实ＩＬＴ在安徽存在提供了可靠的依据。     

鸡传染性喉气管炎病毒的分离鉴定

从平顶山某鸡场患病鸡群中分离到一株病毒，经过鸡胚接种、中和试验、琼扩试验、理化特性和回归试验，确定分离毒为ILTV，分离毒株暂定名为ILT－PDS。     

鸡传染性喉气管炎病毒的分离与鉴定

从发病鸡场中分离到一株ILT毒株。该病毒能使SPF鸡胚100%死亡;攻击非免疫鸡后第3天起发病,发病率100%,死亡率10%。剖检可见与野外病例相同的病现变化。取CAM经超薄切片后,从电镜中观察到该病毒粒子呈六边形,二十面体对称,直径约180～200nm。经免疫保护试验、血清中和试验及理化特性测定,证明该分离物为ILT病毒,暂定名为ILTV-SF株。     

鸡传染性喉气管炎的诊治及病毒分离鉴定

哈尔滨市某养鸡场发生以呼吸道症状为主的传染病，病鸡呼吸困难，张口伸颈喘气，咳嗽，咳出带血的渗出物，发病率９０％，死亡率２．９５％。经临床剖检、病理组织学、琼脂扩散试验及人工接种试验诊断为鸡传染性喉气管炎，并进行了病毒的分离鉴定。     

鸡传染性喉气管炎病毒江苏分离株的分离鉴定

江苏某养殖场28周龄蛋鸡发生以呼吸困难、咳血和产蛋下降为主要症状的疾病。利用特异性引物,从发病鸡喉头及其分泌物中扩增出鸡传染性喉气管炎病毒(infectious laryngotracheitis virus,ILTV)TK基因的1.3 kb大小片段;发病鸡喉头及分泌物接种鸡胚后,在鸡胚绒毛尿囊膜(CAM)上形成痘斑,产生特征性的多核巨细胞和核内包涵体;第3代分离毒的毒价为10-6.2EID50/0.2 mL;分离毒株可被ILT标准阳性血清中和,中和价为1∶40;人工发病试验显示,接种鸡有ILT典型的呼吸道症状和病理变化。以上结果表明,分离病毒为ILTV,将此分离株命名为XZ09。     

鸡传染性喉气管炎病毒内蒙古地方毒株的分离与鉴定

传染性喉气管炎(ILT)是由传染性喉气管炎病毒(ILTV)引起的一种急性呼吸道传染病。近年来，ILT已成为我国养鸡业的主要疫病之一，给养鸡业造成了巨大的经济损失。在内蒙古地区的部分鸡场，也时有ILT的发生。因为ILT恢复鸡及疫苗免疫鸡有长期带毒现象，一旦形成疫区则很难清除。     

1株鸡传染性喉气管炎病毒的分离和鉴定

鸡传染性喉气管炎是危害养鸡业的一种重要的病毒性传染病,各种日龄的鸡均易感。临床表现为呼吸困难,解剖可见喉头和气管出血、充血并有大量黏液渗出为主要病变特征。青海省西宁市某养鸡场饲养的蛋鸡20%出现类似的临床症状,部分鸡死亡,剖检可见喉头气管出血及大量黏液,临床初步诊断为鸡传染性喉气管炎病毒感染。取送检的喉头和气管组织进行实验室病毒分离和鉴定,通过病毒的SPF鸡胚分离、血清学和分子生物学PCR检测,最终确诊该养鸡场发生了鸡传染性喉气管炎病毒感染并分离到致病毒株。     

鸭源禽流感病毒的分离鉴定及特性研究

从湖北某鸭场采集泄殖腔棉拭子20份,通过传统的禽流感病毒分离方法即鸡胚尿囊腔接种法分离到1株鸭源禽流感病毒(AIV).血清学试验表明,该病毒分离株为A型流感病毒,经血凝素亚型鉴定为H9型,与禽流感病毒H9亚型标准阳性血清的血凝抑制(HI)价为8 log2,电镜负染拍照后,可清楚观察到典型的流感病毒粒子形态;致病性试验表明,该流感病毒对鸡表现为较低的致病力.研究表明,水禽,特别是鸭,正日益成为禽流感的高度易感动物,是AIV生态循环中重要的一环.     

Molecular biology of avian infectious laryngotracheitis virus

Infectious laryngotracheitis virus (ILTV) is an alphaherpesvirus that causes an economically important chicken disease, which results in delayed growth, reduced egg production, and also frequently in death of the animals. After acute infection of the upper respiratory tract, the virus can establish latency in the central nervous system, and subsequent reactivations can lead to infection of naive chickens. For prevention of ILT, conventionally attenuated live vaccines are available. However, these vaccine strains are genetically not characterized, and reversions to a virulent phenotype occur. Although molecular analyses of ILTV are hampered by the lack of an optimal cell culture system, the complete nucleotide sequence of the ILTV genome has recently been elucidated, and several ILTV recombinants lacking nonessential, but virulence determining genes have been constructed. Animal trials indicated that genetically engineered stable gene deletion mutants are safe alternatives to the current vaccine strains. Furthermore, since live ILTV vaccines are suitable for fast and inexpensive mass administration, they are promising as vectors for immunogenic proteins of other chicken pathogens. Thus, immunization with ILTV recombinants expressing avian influenza virus hemagglutinin was shown to protect chickens against ILT and fowl plague. Using monospecific antisera and monoclonal antibodies several virion proteins of ILTV have been identified and characterized. Since they include immunogenic envelope glycoproteins, these results can contribute to the improvement of virus diagnostics, and to the development of marker vaccines.     

J亚型禽白血病病毒的分离与鉴定

本研究分别从广西的地方肉鸡及河北、辽宁的蛋鸡中分离到了3株禽白血病病毒.剖检疑似发病鸡只.采集病变的肝脏、脾脏组织,经过RT-PCR检测确定为ALV感染.将病变组织接种CEF细胞,连续传代2次,将细胞上清接种DF-1细胞,p27抗原检测为阳性.同时提取病毒基因组,用H5/ADI和H5/H7两对特异性引物进行PCR扩增,结果3株为ALV-J亚型.进一步设计ALV-J亚型gp85特异性引物进行PCR扩增并测序.结果确认分离到的3株病毒为ALV-J亚型.其gp85序列与标准毒株HPRS-103同源性为96%.同时,用p27单抗进行间接免疫荧光试验,测定毒力.综上所述,我们从广西地方肉鸡巾分离到1株J亚型禽白血病病毒,从河北及辽宁的蛋鸡中分离到2株J亚型禽白血病病毒.     

1株鸡新城疫强毒株的分离鉴定及致病性

从山东省一发病率、死亡率高的肉鸡群中分离到1株病毒,经HA、HI试验和动物回归试验确定所分离的毒株为新城疫病毒,命名为新城疫LVCX株。按常规方法测得LVCX株的MDT、ICPI和IVPI分别为47.4h、1.975和2.85,鸡胚半数致死量LD50为10-9.8。F基因分析表明分离株LVCX为基因Ⅶ型,其多肽裂解位点为112-RRQKRF-117,表明LVCX株为新城疫病毒强毒株。该毒株F基因核苷酸同源性与近几年分离的基因Ⅶ型鸡源毒株同源性在93.5%～98.3%之间;与经典强毒株F48E9和Lasota株的核苷酸和氨基酸同源性分别为85.8%、91.3%和83.3%、88.4%;且与近几年分离的几株鹅源、鸭源核苷酸同源性也较高,在95.2%～96.5%之间。     

一株鸡肾型传染性支气管炎病毒的分离与鉴定

从山东某鸡场疑似肾型传染性支气管炎病死鸡的肾脏中分离到一株病毒,经SPF鸡胚连续传代、血凝试验、鸡新城疫干扰试验、鸡胚矮小化试验、RT—PCR鉴定和动物回归试验,初步确定该病毒为肾型传染性支气管炎病毒,并命名为SD1105株。     

鸡传染性喉气管炎病毒适应性细胞的筛选

为了克服鸡传染性喉气管炎弱毒活疫苗产品制备中存在的缺陷,通过对BHK-21细胞、Vero细胞、DF1细胞、原代鸡胚成纤维细胞(CEF)、原代鸡胚肝细胞、原代鸡胚肾细胞等六种细胞进行病毒适应性培养,采用PCR和免疫荧光(IFA)跟踪检测的方法成功筛选出具有稳定病毒滴度的病毒适应性细胞——鸡胚肝细胞。然后采用新的克隆方法缩短了克隆时长并对筛选的鸡胚肝细胞进行克隆纯化,通过与原代鸡胚肝细胞进行比较,结果显示本试验所采用的克隆方法具有高几率的特点,并且能够克隆出高活性的鸡胚肝细胞,并能够繁殖较高效价的鸡传染性喉气管炎病毒,为解决鸡传染性喉气管炎弱毒疫苗在生产上存在的瓶颈问题提供了重要的基础条件。     

Seroprevalence of avian influenza virus, infectious bronchitis virus, reovirus, avian pneumovirus, infectious laryngotracheitis virus, and avian leukosis virus in Nigerian poultry

Eight poultry farms in Nigeria, including chickens from nine breeder, 14 broiler, 28 pullet, 11 layer, and three cockerel flocks, were tested for antibody seroprevalence to the following poultry viruses of potential economic importance: infectious bronchitis virus (IBV), avian reovirus, avian pneumovirus (APV), infectious laryngotracheitis virus (ILTV), avian influenza virus (AIV), and avian leukosis virus (ALV). Serum samples were collected between 1999 and 2004 and were tested for antibodies using commercial enzyme-linked immunosorbent assay (ELISA) kits. Seroprevalence was very high for IBV (84%); intermediate for reovirus (41%), APV (40%), and ILTV (20%); and very low for ALV (<5%) antibodies. By commercial ELISA, the seroprevalence of antibodies against AIV was, in some flocks, up to 63%. However, more specific assays did not confirm AIV antibodies, indicating that all flocks tested were free of avian influenza antibodies. Birds seemed to be first infected by IBV (at about 7 wk of age), then by reovirus at 12 wk, before they became infected by APV (week 25) and ILTV (week 30). This is the first report of serological evidence of the above viruses in West Africa. Further studies are necessary to assess economic losses due to these avian viruses and the costs and benefits of countermeasures.     

台湾基因Ⅰ型鸡传染性支气管炎病毒SCTW株的分离鉴定及致病性研究

为分离鉴定鸡传染性支气管炎病毒(IBV)及其致病性,本研究通过病料鸡胚接种和鸡胚尿囊液的RT-PCR检测,从四川某养鸡场的发病鸡群中分离出一株IBV.其S1基因测序分析表明,该病毒分离株属于台湾基因Ⅰ型(TWⅠ)IBV,命名为SCTW株,这是中国大陆地区首次分离的TWⅠ型IBV.将该分离株与禽源致病性大肠杆菌(E.coli)分别或混合感染15日龄白羽肉鸡以鉴定其致病性,结果显示:SCTW分离株具有较强的致病性;而且E.coli的混合感染可明显增加SCTW的发病率和病死率,使其组织病理变化更加严重.因此,加强IBV的流行病学调查,做好E.coli的防治,对鸡传染性支气管炎(IB)的防制有重要的意义.