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1.
An outbreak of disease in young pigeons associated with a herpesvirus is reported. The clinical history, macroscopic and microscopic appearance of lesions and virus isolation are described. Most affected birds showed lesions in the upper alimentary tract epithelium as well as in skin, nasal mucosa and salivary glands. Lesions in liver, spleen and pancreas were uncommon. A herpesvirus capable of producing CPE on tissue culture and lesions on chorioallantoic membrane of developing chicken embryos was isolated and described. Inoculation of experimental pigeons with the virus failed to reproduce the disease.  相似文献   

2.
A herpesvirus was isolated from tumours of the ethmoidal mucosa in two of three head of cattle in the State of Kerala, India. The virus designated M40 was cytopathic for a variety of cultured bovine and porcine cells and it did not kill suckling mice or chicken embryos. Sera from tumour-bearing cattle and goats reacted with the M40 virus. Immunofluorescence tests with FITC-conjugated IgG from a bovine monospecific antiserum to bovine herpesvirus 4 (BHV-4) stained the M40 virus specific antigen in infected cells. Experimental infection of goats with the M40 virus did not result in development of tumours. This virus is therefore considered to represent a "passenger" virus. A great similarity was found between restriction patterns of DNAs extracted from M40 virus and the strain 66-P-347, a reference strain of the BHV-4 group.  相似文献   

3.
Ten common kestrels (Falco tinnunculus) were used for this falcon herpes vaccine experiment. Four kestrels were subcutaneously given 1 ml of an attenuated falcon herpesvirus that had originally been isolated from the liver of an American prairie falcon (Falco mexicanus). This virus was then passaged 100 times on chicken embryo fibroblast cells (CEF-cells). Another 4 kestrels were given subcutaneously an inactivated falcon herpesvirus vaccine derived from the same American field strain. This vaccine was concentrated, inactivated by heat and betapropiolactone and emulsified in complete Freund's adjuvans. Two further kestrels served as controls and were not vaccinated. Twenty-one days after vaccination, all 10 kestrels were challenged with passage 3 of the American falcon herpesvirus. The 2 control kestrels died 6 days after challenge and 3 of those given the inactivated herpes vaccine died 9 days after challenge, with typical lesions of herpesvirus inclusion body hepatitis. Before the vaccination experiment, all 10 kestrels were free of serum neutralising antibodies to the falcon herpesvirus. Twenty-one days after vaccination, all 4 kestrels vaccinated with the attenuated vaccine, and one vaccinated with the killed vaccine, had seroconverted, having shown no symptoms to the challenge with a low passage virulent American herpesvirus strain. Following the challenge their antibody titres to falcon herpesvirus increased. No herpesvirus was isolated from any of the cloacal swabs taken during this experiment, indicating that there is no danger for any other birds from the attenuated herpesvirus vaccine. This experiment clearly shows that an attenuated falcon herpesvirus vaccine can protect kestrels from fatal inclusion body hepatitis.  相似文献   

4.
Quail embryo fibroblasts were used to investigate how rabbit and chicken antisera against chicken erythrocytes carrying different B alleles of the major histocompatibility antigens affect the neutralization of herpesvirus of turkeys (HVT). Although the neutralizing activities of these antisera were rather low, the HVT propagated in chicken embryo fibroblasts (CEF) from certain genotypic embryos was neutralized more by the antisera to the corresponding erythrocytes. After absorption of these antisera with homologous erythrocytes, the neutralizing activity of the absorbed sera was reduced slightly. These results reveal that the virion antigens of HVT might be partially associated with the host cell antigens of the fibroblast infected with the virus. The virus grown in these cells might incorporate the host cell antigens, including histocompatibility antigens, into the virion envelope.  相似文献   

5.
A commercial infectious bronchitis virus (IBV) vaccine of the Massachusetts 41 strain was injected in embryonating chicken eggs on embryonation day (ED) 18. The IBV vaccine was pathogenic for embryos, and it was passaged in chicken kidney tissue culture to reduce the pathogenicity. At the 40th tissue culture passage (P40-IBV), the virus became apathogenic for the embryos. Maternal antibody-positive or -negative chicks hatching from eggs injected with P40-IBV developed antibody to IBV and were protected against challenge exposure at 4 weeks of age with virulent Massachusetts 41 IBV. Although P40-IBV protected chicks when administered on ED 18, this virus did not protect chicks well if given at hatch. When combined with the turkey herpesvirus (HVT), P40-IBV given on ED 18 did not interfere with the protection against challenge exposure with virulent Marek's disease virus, nor did the presence of HVT interfere with protection by P40-IBV. Thus, under laboratory conditions, IBV vaccine could be combined with HVT to form a bivalent embryonal vaccine.  相似文献   

6.
An epizootic of Pacheco's disease is reported from a zoo bird population. The infection was introduced by wild-captured Patagonian conures (Cyanoliseus patagonus) despite 61 days of quarantine. The disease affected several parrot species and, interestingly, three out of seven bearded barbets (Lybius dubius). The mortality rate was 30.93%. Autopsy revealed abdominal hyperaemia with liver haemorrhages and, in less rapid cases, yellowish discoloration and fragility of the liver. Death was caused by the collapse of circulation. Histopathology demonstrated liver cell necrosis, disintegration of the lobular structure, and a few intranuclear inclusion bodies. Icosahedral virions were detected by electron microscopy. The virus was isolated in the allantoic cavity of embryonated chicken eggs as well as in chicken embryo fibroblast cell culture. A 281-bp-long fragment of psittacid herpesvirus DNA was detected by PCR in cell culture material and liver samples of the affected birds. To our knowledge this is the first report of Pacheco's disease in bearded barbets as well as the first occurrence of Pacheco's disease in Hungary.  相似文献   

7.
采用PCR方法，以传染性贫血病毒(CIAV)DNA为模板，扩增并克隆了CIAV的VP1、VP2基因，并进行了序列分析。经基因修饰，将这两个基因分别加上表达元件后连接作为目的基因。通过同源重组技术，将目的基因插入到火鸡疱疹病毒(HVT)gC基因区，构建了一株含CIAV VP1、VP2基因表达单元的重组HVT(VP1VP2-rHVT)：体内、体外传代结果表明该重组病毒性状稳定。采用PCR扩增及Southem blot杂交检测，证实了CIAV VP1、VP2基因的插入。  相似文献   

8.
为研究具有不同抗性的马立克氏病(MD)疫苗免疫鸡羽髓后,疫苗毒和超强毒(vvMDV)的复制动力学及两种病毒载量的相关性,本实验对经火鸡疱疹病毒(HVT)FC126疫苗株免疫1周后(1wpv),攻击vvMDV Md5株G3系和G7系鸡羽髓中的HVT和vvMDV载量进行定量检测及相关性分析。结果显示,G3系和G7系鸡群羽髓中的vvMDV载量始终高于疫苗毒。其中,G3系鸡群在免疫和攻毒后的相同时间内,疫苗毒与vvMDV载量的消长规律基本一致,均在感染后第4周(4wpi)出现峰值,6wpi降至最低水平,两种病毒载量多表现为正相关,6wpv～8wpv为持续显著正相关;G7系的两种病毒的复制动力学存在差异:vvMDV载量从攻毒后第6周呈增长趋势,而疫苗毒在4wpv出现峰值后迅速下降,两种病毒载量多表现为负相关。本研究表明,免疫遗传基因在对病毒的抵抗中起主要作用,为MDV的感染机制和疫苗免疫机理的研究提供实验依据。  相似文献   

9.
Four tests of an inactivated emulsified vaccine against a herpesvirus infection (Pacheco's disease) in bodgerigars demonstrated that an effective vaccine could be produced with concentrated virus. Virus was propagated in chicken kidney cells, and cells and fluid were harvested 3 to 5 days after inoculation and sonicated. The virus was concentrated 100 x by centrifugation to produce a multiple emulsion vaccine that was protective against IM challenge exposure with live virus. The serologic response after vaccination was negligible, and many survivors to virus challenge exposure did not show a positive titer.  相似文献   

10.
鸭疱疹病毒Ⅱ型（暂定名）的分离鉴定   总被引：11，自引：3，他引：8  
自1990年以来，在福建、浙江和广东等省发生一种以双翅羽毛管淤血呈紫黑色、断裂和脱落以及皮下、脏器（肝脏、胰脏）和肠道（十二指肠、直肠和盲肠）出血为主要特征的新的鸭传染病，暂定名为鸭出血症。我们对从自然感染该病典型病死番鸭脏器中获得的1株含2种病毒粒子（直径大小分别为30－40mm和80－120mm)的分离物，以Ⅰ型雏鸭病毒性肝炎标准阳性血清进行连续4代中和后接种番鸭胚，收集死亡番鸭胚胚液进行病毒纯化、负染、电镜观察和SPF鸡胚接种试验证明获得单一病毒分离株（定名为鸭出血症病毒）。该病毒为不耐酸、不耐碱、不耐热、对氯仿处理敏感、核酸类型为双股DNA的有囊膜病毒，直径为80－150nm；对番鸭胚、鹅胚、麻鸭胚、半番鸭胚、北京鸭胚和SPF鸡胚的致 死率分别为100％、100％、78．3％、60％、82．1％和0％；对10－11日龄番鸭胚的ELD50为10^-7.78/0.2ml；无血凝活性，不凝集“O”型人、鸭、鸡、鹅、家兔、小鼠，豚鼠、猪和绵羊红细胞；经血清中和试验证明该病毒与Ⅰ型雏鸭肝炎病毒、雏番鸭细小病毒、雏鹅细小病毒、鸭瘟病毒无血清学相关性。据以上结果可将该病毒确定为疱疹病毒科成员，但鉴于其与鸭瘟病毒（鸭疱疹病毒Ⅰ型）无血清学相关性，则暂定名为鸭疱疹病毒Ⅱ型，此为国内外首次报道。  相似文献   

11.
DNA has been isolated from herpesvirus of turkeys (HVT) virions and used to construct a partial gene library in pBR-322. The recombinants have been characterized and shown to contain HVT DNA inserts. A representative recombinant containing a 5.9-kilobase HindIII fragment was used as a probe to quantitate the yields of HVT DNA in vitro and to follow the kinetics of viral DNA replication. The data shown that in chicken fibroblasts, viral DNA synthesis initiates by about 12-14 hr postinfection and that the yield of progeny virus plateaus at 28-30 hr postinfection. Based upon quantitative hybridization to cloned DNA probes, we estimate that approximately 2000 HVT genomes are produced per infected cell in vitro; however, in vivo in persistently infected turkeys, the number of viral genomes was below the level of detection by Southern blotting.  相似文献   

12.
The production of antibodies in pigs to 11 herpesviruses was investigated in relation to their ability to cross-react with Aujeszky's disease virus (suid herpesvirus 1--SHV1). Of the herpesviruses tested only two, sheep herpesvirus (caprine herpesvirus 1) and dog herpesvirus (canid herpesvirus 1), failed to produce homologous virus antibodies. Only the antibodies to bovine herpesvirus 1 (BHV1) produced a cross-reaction by SHV1 enzyme-linked immunosorbent assay (ELISA). No SHV1 neutralizing antibodies were detected in any of the herpesvirus antisera. A cross-reaction with SHV1 by a serum from a pig naturally infected with BHV1 or with any of the other herpesviruses tested was considered unlikely.  相似文献   

13.
Adaptation of Marek's disease virus to the Vero continuous cell line   总被引：2，自引：0，他引：2  
Marek's disease virus (MDV) is a highly infectious, cell-associated oncogenic herpesvirus. Production of MD vaccines has been limited to primary chicken and duck embryo fibroblast (CEF and DEF) cultures. These have a limited life span and cannot be readily stored in liquid nitrogen. Moreover, the need to prepare CEF and DEF cells on a regular basis from 10 to 11 day-old embryos derived from a flock that must be tested continuously for the presence of avian pathogens adds to the cost of vaccine production. A continuous cell line that would support MDV replication could have significant advantages for the rapid large-scale preparation of MD vaccines. In this report, we describe the adaptation to growth of CEF-grown preparations of serotype 1 and serotype 3 (herpesvirus of turkeys; HVT) strains of MDV in cells of the Vero continuous cell line. Although both viruses produced typical CPE, higher levels of infectious progeny and more extensive virus-specific immunofluorescence were obtained for HVT than for the serotype 1 virus. PCR and pulsed field electrophoresis (PFE) analysis of the DNA from Vero cells infected with either virus confirmed the presence of virus-specific DNA.  相似文献   

14.
A genomic library of infectious laryngotracheitis virus (ILTV) DNA BamH1 fragments was prepared and two cloned fragments were evaluated for their potential as probes for the detection of ILTV infected cells. The virus was purified by a modified sucrose density gradient procedure for the isolation of pure ILTV DNA. A genomic library was constructed using BamH1-digested ILTV DNA and pGEM7 as a vector. A 1.1 kb cloned BamH1 fragment of ILTV DNA was tested in a slot or dot blot assay for the detection of ILTV infected cells. The limit of detection for this probe was at least 0.12 ng of pure ILTV DNA. The probe was able to identify both chicken embryo liver (CELi) cells and choriallantoic membranes infected with ILTV. Chicken embryo liver cells infected with several field isolates and a vaccine strain of ILTV were positive by dot blot analysis using this probe. Some qualitative differences in the degree of hybridization to cells infected by different ILTV isolates were observed. Uninfected cells and cells infected with fowlpox virus, turkey herpesvirus, Marek's disease virus or Newcastle disease virus were negative by the same assay. Compared with the 1.1 kb fragment, a larger 6 kb cloned BamH1 fragment of ILTV DNA showed a stronger hybridization signal to DNA from ILTV infected cells.  相似文献   

15.
Psittacid herpesvirus (PsHV) was isolated from 41 birds kept in captivity in Belo Horizonte, Minas Gerais/Brazil using chicken embryo fibroblasts (CEF) cell cultures. For this study, leukocytes or cloacal swabs of live birds were used. Also, portions of liver, spleen or kidney from birds collected at necropsy were utilized for these tests. PCR tests confirmed the presence of PsHV in 100% of samples. Thirty-three of the PCR products were sequenced and the results disclosed a 99% and 100% identity when compared with other sequences PsHV-1 (AY372243.1 and AF261756.1), previously deposited in GenBank. In addition, histopathology was performed and 19 of the 29 birds contained random multifocal lymphoplasmacytic hepatitis with necrotic foci, suggestive of viral infection. Three samples were examined by electron microscopy to visualize the viral particles obtained from cell culture. The viral structures measured 269 nm in average, had envelopes with an icosahedral capsid and tegument, consistent with herpesvirus. Thus, a total of 41 isolates were obtained from PsHV cell cultivation in CEF, confirming the circulation of the virus between parrots kept in captivity in Belo Horizonte, and affirming the importance of further studies in this area.  相似文献   

16.
Dilution of Marek's disease (MD) vaccines is a common practice in the field to reduce the cost associated with vaccination. In this study we have evaluated the effect of diluting MD vaccines on the protection against MD, vaccine and challenge MD virus (MDV) kinetics, and body weight when challenged with strains Md5 (very virulent MDV) and 648A (very virulent plus MDV) by contact at day of age. The following four vaccination protocols were evaluated in meat-type chickens: turkey herpesvirus (HVT) at manufacturer-recommended full dose; HVT diluted 1:10; HVT + SB-1 at the manufacturer-recommended full dose; and HVT + SB-1 diluted 1:10 for HVT and 1:5 for SB-1. Vaccine was administered at hatch subcutaneously. One-day-old chickens were placed in floor pens and housed together with ten 15-day-old chickens that had been previously inoculated with 500 PFU of either Md5 or 648A MDV strains. Chickens were individually identified with wing bands, and for each chicken samples of feather pulp and blood were collected at 1, 3, and 8 wk posthatch. Body weights were recorded at 8 wk for every chicken. Viral DNA load of wild-type MDV, SB-1, and HVT were evaluated by real time-PCR. Our results showed that dilution of MD vaccines can lead to reduced MD protection, reduced relative body weights, reduced vaccine DNA during the first 3 wk, and increased MDV DNA load. The detrimental effect of vaccine dilution was more evident in females than in males and was more evident when the challenge virus was 648A. However, lower relative body weights and higher MDV DNA load could be detected in chickens challenged with strain Md5, even in the absence of obvious differences in protection.  相似文献   

17.
The major histocompatibility complex (MHC) is a part of the immune system which presents epitopes of intracellular antigens on the cell surface. MHC molecules have receptor-ligand binding affinities with T lymphocytes, permitting the latter to detect foreign intracellular infectious agents. Some pathogens, such as herpesviruses, have developed strategies of evading the host response by MHC. This pressure on the immune system brought, in turn, improvements in the antigen-presenting pathway, for example through the effect of interferon (IFN), which can upregulate MHC expression. The main objective of this work was on the one hand, to determine the abilities of three strains of Marek's disease virus (MDV), a chicken herpesvirus, in interfering with the expression of MHC class I molecules in chicken embryo fibroblasts. On the other hand, we analyzed the ability of IFN to reinstate this important immune capability to the infected cells. Our results show that only an oncogenic serotype 1 strain of MDV (RB1B) was able to markedly decrease MHC class I expression, and that addition of IFN reversed this MDV effect.  相似文献   

18.
A concurrent infection of chickens with infectious laryngotracheitis virus (ILTV), a herpesvirus, and fowlpox virus (FWPV), an avipoxvirus, is described. Two techniques, an immunohistochemistry (IHC) technique and a multiplex polymerase chain reaction (PCR), were used to examine 11 tissue samples from chickens clinically diagnosed as FWPV-infected, but only IHC was used to examine six tissue-paraffin blocks prepared from turkeys suspected of having FWPV infection. By multiplex PCR, both FWPV and ILTV were detected from three chicken samples (FI-90, FI-93, and FI-94); both FWPV and ILTV were detected from only two samples (FI-93 and FI-94) by IHC. All chicken samples were positive for FWPV by both PCR and IHC. Viral DNA from these samples was further confirmed by restriction enzyme analysis. When turkey samples were analyzed by the double-stain IHC, all six samples showed the presence of FWPV antigens, but no ILTV antigens. The double IHC technique, using monoclonal antibodies against FWPV and ILTV, was successful in simultaneous demonstration of specific FWPV and ILTV antigens colocalized in infected tissue samples as well as within individual cells. This paper emphasizes the importance of reliable tests that detect specifically the presence of ILTV and FWPV in infected tissue samples. The multiplex PCR assay holds potential to be versatile, rapid, and more sensitive (100%) than IHC (67%) for the simultaneous detection of two different avian viruses. Furthermore, the presence of mixed infection should always be kept in mind in the virologic analysis of respiratory sickness of poultry.  相似文献   

19.
Hemagglutination activity, structural protein profiles and neutralization assays were used in a comparative study of bovine herpesvirus 1 strains from the U.S.A., Canada, Great Britain, Denmark and Malaysia with equine, feline and human herpesviruses in order to further characterize the bovine herpesvirus 1 hemagglutinin. Bovine herpesvirus 1 strains of different geographical origins all showed hemagglutinating activity for mouse erythrocytes; furthermore, feline herpesvirus 1 was also shown to hemagglutinate mouse erythrocytes. Analyses of partly purified viruses showed that a distinctive and specific polypeptides profile is associated with each species of herpesviruses used in our study; strains of bovine herpesvirus 1 from North America, Europe and Southeast Asia however, presented a remarkable similarity as to their electrophoretic protein patterns. A protein similar to the 97-kDa bovine viral hemagglutinin was not identified with the hemagglutinating feline herpesvirus. An important neutralization epitope on the bovine viral hemagglutinin was also not found on feline, equine and human herpesviruses but was identified on all bovine strains tested from North America, Europe and Southeast Asia stressing the importance of the bovine hemagglutinin for eventual prophylactic purposes.  相似文献   

20.
A multiplex polymerase chain reaction (PCR) method coupled with a restriction analysis of PCR products (PCR with restriction fragment length polymorphism) was developed for the simultaneous detection of bovine herpesvirus 1, bovine herpesvirus 2, and bovine herpesvirus 4 infections. The specificity, sensitivity, and practical diagnostic applicability of this method were evaluated. This assay may be also adapted to the diagnosis of suid herpesvirus 1 and equine herpesviruses 1 and 3 and could become a powerful diagnostic tool.  相似文献   

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