鸡传染性支气管炎病毒的分离和鉴定

为掌握发病鸡场的致病原,将临床病料接种SPF鸡胚分离得到一株病毒,通过胚体病变特征、血凝试验、RT-PCR检测、动物回归试验等对该病毒进行了鉴定,结果显示:病料处理接种鸡胚后48~144 h内鸡胚全部死亡,剖检死亡鸡胚可见胚体存在蜷缩、发育矮小等特异性病痕,收获的鸡胚尿囊液无血凝性,RT-PCR检测为鸡传染性支气管炎病毒阳性,动物回归试验中接种的SPF雏鸡可复制出现鸡传染性支气管炎的典型症状。     

一株肾型鸡传染性支气管炎病毒的初步分离鉴定

从哈尔滨市某肉鸡养殖场疑似传染性支气管炎的病死鸡中分离到1株肾型IBV,并对其进行鸡胚矮小化、血凝性、电镜下特征、新城疫干扰试验、致病性等生物学鉴定和N基因的RT-PCR鉴定。结果表明,该病毒分离株在鸡胚上传至第四代(F)4开始出现死亡或侏儒胚;病毒不凝集鸡红细胞;透射电镜下可见多呈球形、直径约80～120nm的病毒粒子,具有冠状病毒的典型形态特点;该病毒可干扰新城疫LaSota株在鸡胚中的增殖;将分离毒第4代尿囊液接种于6日龄雏鸡,7d后开始出现死亡,死亡率高达67%(6/9),病死鸡剖解后可见肾脏明显肿大、苍白,具有传染性支气管炎的典型病变;分离毒第5代尿囊液经N基因特异性RT-PCR获得大小约438bp的目的片断。初步确定所分离病毒为肾型IBV。     

鸡减蛋综合症的临床鉴别诊断

1993年2月,我局种禽场饲养的迪卡父母代种鸡发生了减蛋综合症。在确诊过程中感到鸡减蛋综合症与非典型新城疫、传染性支气管炎、脂肪肝综合症、钙磷缺乏症都是鸡的流行病,临床都表现产软皮蛋、畸形蛋、蛋壳颜色变浅、产蛋率下降等症状,很容易在实践中误诊,必须做好鉴别诊断。 与非典型新城疫的区别:非典型新城疫也能引起产蛋下降,产软皮蛋,同时在鸡群中出现病死鸡,而对死鸡进行剖检发现喉头气管粘膜、腺胃乳头、盲肠扁桃体、直肠及泄殖腔等处粘膜出血,产蛋率下降相对大些,而减蛋综合症无此现象。另外,减蛋综合症在血凝抑制试验中,抗体离散,抗体上升较快,抗体效价可达2～1024,而非典型新城疫的血凝抑制价为2～512。     

传染性支气管炎病毒Jin13株的特性研究

<正>Jin13株是从郑州郊区出现呼吸道症状的雏鸡群中分离到的1株流行毒株,可引起鸡胚死亡、出现侏儒胚、新城疫干扰试验阳性、无血凝性,经形态学、理化特性、特异性鉴定为鸡传染性支气管炎病毒(IBV)。     

一株鸡传染性支气管炎病毒的分离和鉴定

对枣庄市某养鸡场送检的疑似鸡传染性支气管炎病料进行分离和鉴定,通过发病鸡场病鸡临床症状观察,病理解剖,实验室PCR检测,鸡胚致病性试验、血凝实验,对鸡新城疫病毒的干扰试验、动物回归试验等,一系列试验结果表明,该病的临床症状和病理变化典型,实验室PCR检测为鸡传染性支气管炎阳性,病料处理接鸡胚后,24-48h鸡胚全部死亡,死亡鸡胚表现失水、蜷缩、发育小等特异性病痕,收获的鸡胚尿囊液无血凝性,分离毒对NDV感染有干扰作用;动物回归试验接种SPF雏鸡可复制出现鸡传染性支气管炎的典型症状。表明该鸡场确实发生了鸡传染性支气管炎病毒的感染,春季是该病的高发季节,应加强对该病的诊断和防控。     

鸡肾型传染性支气管炎病毒的分离鉴定

2012年3月,新郑市某蛋鸡场发生了1例疑似肾型传染性支气管炎病,取剖检病鸡的气管和肺脏组织经过无菌处理,分离到1株病毒。为确定该病毒,应用病毒分离、血凝试验、鸡胚矮小化试验、干扰新城疫病毒复制试验、琼脂凝胶扩散试验、RT-PCR鉴定和动物回归试验方法鉴定,结果均符合鸡肾型传染性支气管病毒的生理特性。通过检查结果结合临床、剖检症状,确认该病毒就是鸡肾传染性支气管炎病毒。     

鸡肾型传染性支气管炎病毒的分离鉴定

从安徽省巢湖地区鸡群中出现的以肾肿大为主要特征的呼吸道疾病的病例中分离到1株病毒,易感雏鸡,病死鸡出现肾肿大、苍白呈花斑状、大量尿酸盐沉积;鸡胚连续盲传至第5代时开始出现死亡和侏儒胚.电镜观察可见80～120nm的病毒颗粒.分离病毒在鸡胚上可干扰新城疫病毒clone-30株的增殖.上述试验证实所分离的病毒为鸡肾型传染性支气管炎病毒,暂定名为NIBV-AH99.     

鸡肾型传染性支气管炎病毒JH9801株的分离鉴定

从天津市某肉用鸡场疑似肾型传染性支气管炎（NIB）病鸡中取肾组织，按常规处理后接种9－10日龄鸡胚，连续传代培养至第7代，并对4－7代分离毒株的致病性、血凝性、EID50及对DNV的干扰性和乙醚敏感性进行测试，同时进行了动物回归试验。结果表明，4－7代分离毒株可使85％－90％鸡胚于接种后8－9d死亡，多数死胚和残存活胚胚体出血、蜷缩、矮化等具有IBV感染特征；该分离毒株无直接血凝性，但经10g/L胰酶处理后可集鸡红细胞；分离毒株对乙醚敏感；动物回归试验中有65％的感染鸡在15d内发病或死亡。剖检病死鸡可肾苍白、肿胀，肾小管内充塞大量尿酸盐，外观呈菜花样。经鉴定，分离的病毒株JH9801为鸡肾型传染性支气管炎病毒（NIBV）。     

山东地区鸡肾型传染性支气管炎病毒的分离鉴定及防治

山东临沂地区某鸡场25日龄鸡群发病,临床表现为气管啰音、咳嗽、打喷嚏,剖检肾脏有大量尿酸盐沉积,疑似感染鸡肾型传染性支气管炎。为了探究发病鸡群的病因,试验选取120只该场疑似鸡肾型传染性气管炎病毒致死的病死鸡,进行剖检,取肾、肺和气管等组织器官经过无菌处理后,分离得到若干株病毒,通过临床检查、病毒分离、血凝试验、鸡胚传代试验等方法鉴定。试验表明,所得结果与鸡肾型传染性支气管病毒的临床特征和特性基本一致,说明引起该鸡群发病的病原为鸡肾型传染性支气管炎病毒。     

鸡传染性支气管炎病毒BJ0903株的分离鉴定

从北京某养鸡场疑似肾型传染性支气管炎病死鸡的肾脏和肺脏组织中分离到一株病毒,经SPF鸡胚连续传代、血凝试验、鸡胚矮小试验、干扰新城疫病毒复制试验、PCR鉴定和动物回归试验,初步确定该病毒为鸡传染性支气管炎病毒,命名为BJ0903株。     

鸡腺胃病变型传染性支气管炎病毒感染试验

本文采用腺胃病变型传染性支气管炎患病鸡的腺胃病料和H95株分离株尿囊液毒,对不同品种、不同日龄的易感鸡,采用不同的感染途径进行感染,对其增重、死亡等数据进行统计分析,结果表明:供试不同品种的鸡在不同的感染途径下,采用腺胃病料和鸡胚尿囊液毒分别感染,均可引起不同程度的感染发病,并出现和自然病例相同的症状和典型的病理变化。随日龄的增长,其易感率和死亡率呈下降趋势。从感染死亡鸡中可重新回收到相应的病毒,发病耐过的鸡可产生特异性抗体。     

Serological monitoring on layer farms with specific pathogen-free chickens

To monitor the existence of avian pathogens in laying chicken flocks, specific pathogen-free (SPF) chickens were introduced into two layer farms and reared with laying hens for 12 months. SPF chickens were bled several times after their introduction and examined for their sero-conversion to avian pathogens. As a result, antibodies to eight or ten kinds of pathogens were detected in SPF chickens on each farm. Antibodies to infectious bronchitis virus (IBV), avian nephritis virus, Mycoplasma gallisepticum and M. synoviae were detected early within the first month. Antibody titer to IBV suggested that the laying chickens were infected with IBV repeatedly during the experiment on both farms. However, antibodies to infectious bursal disease virus and 6 pathogens were not detected.     

THE ISOLATION OF LENTOGENIC STRAINS OF NEWCASTLE DISEASE VIRUS IN AUSTRALIA

SUMMARY Twelve isolations of Newcastle disease virus were made from 77 clinical samples from chickens with conjunctivitis, respiratory disease, proventriculitis and bursal atrophy. Nine of the Isolations were made from chickens with conjunctivitis. The viruses were identified as Newcastle disease virus by inhibition of their haemagglutinins with specific antiserum to Newcastle disease virus. The viruses failed to kill chicken embryos after inoculation into the allantoic cavity and they were judged to be lentogenic strains. There was no evidence that the Newcastle disease viruses were responsible for any of the clinical conditions from which they were isolated. The presence of other agents in 10 of the samples was indicated by reduced production of haemagglutinin in allantoic fluids of infected embryos, by deaths of infected embryos, by the production of cytopathic changes in avian cell cultures and by electron microscopy. Three isolations of infectious bronchitis virus, 2 of avian adenovirus and one of avian reovirus were made. Other samples were suspected of containing infectious bronchitis virus and mycoplasmas, but these were not isolated. The Newcastle disease viruses failed to produce plaques in chicken embryo fibroblast cell cultures and they were separated from the contaminating agents by haemagglutination and elution followed by passage at terminal dilution in chick embryos. No Newcastle disease virus was isolated from 60 caecal tonsils and 60 lung samples from 9-week-old broiler chickens. Eight lung samples yielded mycoplasmas that caused haemadsorption in chicken cell cultures. The mycoplasmas were probably Mycoplasma gallisepticum.     

Sporadic congenital transmission of avian leukosis virus in hens discharging the virus into the oviducts.

The efficacy of the albumen test for infectious avian leukosis virus (ALV) was examined in detecting congenitally transmitting hens. Seventy-three White Leghorn non-viremic hens with antibody to ALV were used. Eleven of the hens shed infectious ALV into their egg albumen, whereas only 7 of the 11 ALV-positive hens shed ALV antigens. The egg albumen test for infectious ALV was shown to be more effective in detecting the congenitally transmitting hens than that for ALV antigens. Then, twenty of the 62 hens which shed no infectious ALV into the albumen were studied for transmission of ALV to their embryos and for discharging ALV into the oviduct and vagina. Six of the 50 embryos from 4 hens were found to be infected with ALV but all of the 227 embryos from remaining 16 hens were free from the infection. Discharge of the virus into the oviduct and vagina was found both in the 4 transmitting hens and in 6 of the 16 non-transmitting hens. These results suggest that the hens discharging ALV into the oviduct, even though they do not shed ALV into egg albumen, may transmit the virus sporadically to their embryos.     

1株肾型鸡传染性支气管炎病毒的鉴定

鸡传染性支气管炎病毒(IBV)具有不同致病特性,将IBV XDC-2株接种9日龄SPF鸡胚培养,可引起鸡胚死亡和出现侏儒胚,病毒EID50达5×10-5.33/mL。将IBV XDC-2株接种18日龄SPF鸡,饲养观察14 d,病鸡临床症状表现为:精神沉郁,羽毛凌乱,双翅下垂,轻微腹泻,多数拉白色水样稀粪。病死鸡出现肾肿大、呈花斑状、大量尿酸盐沉积。鸡发病率为100%,死亡率为25%。死亡鸡肺脏、肾组织制作组织切片,发现病理变化明显,主要为:肾小管扩张,上皮细胞呈玻璃样变性,部分管腔内可见坏死脱落之上皮细胞,于肾间质可见大量单核细胞浸润,肾间质有充血、出血现象;肺内动脉、毛细血管充血,淋巴细胞浸润。死亡鸡肺脏、肾组织接种鸡胚分离病毒,RT-PCR检测结果为阳性,表明该分离株为鸡传染性支气管炎病毒,具有很强的嗜肾性。     

鸡肾型IBV的分离及其N基因的克隆与测序

通过病毒形态学观察、血凝试验、病毒干扰实验、动物回归实验等分离鉴定了1株鸡肾型传染性支气管炎病毒.利用RT-PCR技术对分离毒株的N基因进行了扩增,经克隆、序列测定和分析,证实分离株为肾型IBV.