Pathogenicity of attenuated peste des petits ruminants virus in sheep and goats

Progressive loss of virulence for goat kids was noticed when peste des petits ruminants (PPR) virus was passaged in Vero cells. While goats inoculated with the 60th passage suffered from the clinical PPR disease and mortality, goats inoculated with the 80th passage did not show any sign of the disease. If the progressive loss of virulence of the virus with passage continues, it will not be long before a homologous PPR vaccine will be obtained at the National Veterinary Institute, Vom.     

An immunohistochemical study of the pneumonia caused by peste des petits ruminants virus

Ten goats were inoculated with peste des petits ruminants virus, a paramyxovirus closely related to rinderpest virus. All goats developed severe clinical disease, 8/10 having coughing or dyspnea as prominent clinical signs. In addition, all of the goats had stomatitis and diarrhea. Histopathologic and immunohistochemical studies were done only on the respiratory tracts. Pathologic changes ranged from mild multifocal bronchiolitis and bronchitis to severe bronchointerstitial pneumonia. Lesions were more severe in anteroventral than caudal lobes. The histologic nature of the viral process in the goat lungs had many features in common with the processes of pneumonia in dogs, due to canine distemper, or pneumonia in human beings, due to measles virus. Immunohistochemical staining of formalin-fixed, paraffin-embedded respiratory tract tissue was performed using an indirect system with rabbit anti-rinderpest virus serum, biotinylated anti-rabbit antibody, streptavidin-alkaline phosphatase, and nitroblue tetrazolium chromogen. Staining was sensitive, highlighting the presence of viral antigen in both lung and trachea of all goats. Viral antigen was found in both cytoplasm and nucleus of tracheal, bronchial, and bronchiolar epithelial cells, type II pneumocytes, syncytial cells, and alveolar macrophages. In general, the amount of staining correlated directly with the severity of the inflammatory process.     

Pathogenicity of peste des petits ruminants virus isolated from Egyptian goats in Egypt

2 Egyptian goats and Boscat rabbits were experimentally inoculated with peste des petits ruminants (PPR) local Egyptian strain (PPR, Egypt 87). The inoculated animals contracted the disease with minor clinical manifestations, accompanied by rise of neutralizing antibodies to PPR virus. Virus was isolated from ocular and nasal secretions, buffy coat, spleen, and liver. No contact infection was observed between inoculated and healthy goats.     

The isolation of peste des petits ruminants virus from Nigerian sheep and goats.

Four isolates of peste des petits ruminants virus were obtained from sick Nigerian sheep and goats. One was identical antigenically with the prototype Senegalese strain. A cross relationship was found between peste des petits ruminants virus and rinderpest virus based on neutralisation in vitro.     

小反刍兽疫的研究进展

概述了小反刍兽疫的易感动物、临床症状及病原的理化特征和基因组结构，重点阐述了病毒6种结构蛋白的大小和组成、小反刍兽疫病毒的分离培养、血清学及分子生物学诊断技术，并对其传统疫苗以及新型基因工程疫苗的研制进行了详细论述，以为该病的流行病学研究、诊断和免疫防制提供参考。     

Prevalence of peste des petits ruminants among sheep and goats in India

This study measured the clinical prevalence of peste des petits ruminants (PPR) among sheep and goats in India between 2003 and 2009 by analyzing clinical samples from suspected cases of PPR that were submitted to the Rinderpest and Allied Disease Laboratory, Division of Virology, IVRI, Mukteswar for PPR diagnosis. PPR outbreaks were confirmed by detecting PPR virus (PPRV)-specific antigen in the clinical samples. Clinical samples (blood, nasal swabs, spleen, lymph node, kidney, liver, intestine, and pooled tissue materials) were taken from a total of 592 sheep and 912 goats in different states of India and screened for the presence of PPRV antigen using a monoclonal antibody-based sandwich ELISA kit. A total of 20, 38, and 11 laboratory-confirmed PPR outbreaks occurred among sheep, goat, and combined sheep and goat populations, respectively. Our findings provide evidence of widespread PPR endemicity in India. The underlying reasons could be variations in husbandry practices in different geographical regions, agro-climatic conditions, and livestock migration. Furthermore, decrease in the number of PPR outbreaks over time might be due to the effectiveness of current live PPR vaccines and timely vaccination of target species. Vaccination against PPR has been practiced in India since 2002 to control this disease.     

Evidence of identification of peste des petits ruminants from goats in Egypt

Peste des petits ruminants virus was isolated from young goats in an outbreak of the disease for the first time in Egypt. Affected goats showed symptoms simulating rinderpest, disease in cattle. The mortality rate was about 30%, and morbidity reached 90%. History, clinical symptoms, postmortem lesions, and diagnosis were discussed.     

Experimental infection of domestic pigs with the virus of peste des petits ruminants

Summary Pigs could be subclinically infected with PPRV by inoculation or contact with infected goats. There was no evidence that the virus could spread to uninfected pigs or goats and pigs are not considered important in the epidemiology of PPRV.

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Infección Experimental De Cerdos Domésticos Con El Virus De Estomatitis Ulcerativa O Peste Des Petits Ruminants

Resumen Fué posible infectar cerdos subclinicamente con el virus de estomatitis ulcerativa o peste des petits ruminants, mediante inoculación o contacto con cabras infectadas. No hubo evidencia de que el virus pasara o pudiera infectar cerdos y cabras sanas. Se concluye, que los cerdos no se consideran importantes en la epidemiología de la estomatitis ulcerativa.

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Infection Experimentale De Porcs Domestiques Par Le Virus De La Peste Des Petits Ruminants

Résumé Les porcs mis au contact de chèvres atteintes de cette affection ou infectés par inoculation avec le virus de la maladie, peuvent présenter des signes sub-cliniques de l'affection.Il n'est pas évident que le virus puisse alors atteindre des porcs ou des chèvres sains; les porcs ne sont pas considérés comme pouvant jouer un rôle important dans l'épidémiologie de la P.P.R.

     

Experimental infection of alpine goats with a Moroccan strain of peste des petits ruminants virus (PPRV)

Peste des petits ruminants virus (PPRV) recently caused a serious outbreak of disease in Moroccan sheep and goats. Alpine goats were highly susceptible to PPRV with mortality rates approaching 100%, as opposed to local breeds of sheep which were less susceptible to the disease. The relative susceptibility of alpine goats was investigated through an experimental infection study with the Moroccan strain of PPRV. Severe clinical signs were observed in the alpine goats with virus being excreted through ocular, nasal and oral routes. No difference in the severity of the disease in goats was observed with different inoculation routes and transmission of the virus by direct contact was confirmed. This study confirmed the susceptibility of the alpine goat to PPRV infection and describes a challenge protocol that effectively and consistently reproduced severe clinical signs of PPR in experimentally infected goats.     

A comparative study of peste des petits ruminants and Kata in West African dwarf goats

Summary Experimental infections of West African Dwarf goats with Peste des Petits Ruminants (PPR) and Kata were indistinguishable clinically and pathologically. Goats convalescent from Kata resisted infection with rinderpest virus. Heterologous stimulation of secondary antibody response was observed.

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Sumario Las infecciones experimentales de cabras enanas de Africa Occidental con la peste de los peque?os ruminantes y con Kata fueron clinicamente y patoligicamente indistinguibles. Cabras que convalecieron de Kata resistieron a la infección con el virus de la peste bovina. Se observó una estimulación heteróloga de la respuesta inmunitaria secundaria.

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Résumé L’infection expérimentale de chèvres naines de l’Afrique de l’Ouest par le virus de la peste des petits ruminants (PPR) et par le virus du Kata a montré que les deux maladies ne présentaient pas de différences cliniques ni pathologiques. Des chèvres convalescentes de Kata ont résisté à l’infection par le virus de la peste bovine. Une stimulation hétérologue de la réponse d’anticorps secondaires a été observée.

     

Experimental studies on immunosuppressive effects of peste des petits ruminants (PPR) virus in goats

Effect of virulent and attenuated peste des petits ruminants (PPR) virus on the immune response to nonspecific antigen (ovalbumin) was investigated. Clinical and serological responses were monitored in goats administered with ovalbumin concurrently with either PPR vaccine or virulent virus. Study showed that PPR virulent virus causes marked immunosuppression as evidenced by leukopenia, lymphopenia, and reduced early antibody response to both specific and nonspecific antigen. These observations were predominant particularly during acute phase of disease (4-10 days post-infection). On the other hand, the vaccine virus induced only a transient lymphopenia without significantly affecting the immune response to nonspecific antigen or to itself during this period. Further, the antibody levels to ovalbumin in the group administered with virulent PPRV increased significantly between days 28 and 35 post-infection in comparison to the titers in other two groups given with either ovalbumin alone or in combination with vaccine.     

小反刍兽疫病毒H基因的原核表达与鉴定

根据GenBank中已发表的小反刍兽疫病毒(PPRV)Nigeria 75/1株的H基因序列,设计上下游引物并添加BamH I酶切位点,以含有小反刍兽疫病毒H基因的Topo-PPRVH质粒为模板进行PCR扩增,扩增产物克隆于pEASY-T载体中,用BamH I单酶切后将目的片段连接到原核表达载体pET-32a(+)中,核酸序列分析证明.成功构建了PPRV H原核表达质粒pET-32a-H.将pET-32a-H重组质粒转化大肠杆茵 BL21(DE3)进行融合表达.经SDS-PAGE电泳,可见H蛋白获得了高效表达,融合蛋白的分子量约为87 Ku,表达产物以包涵体的形式存在,其表达量达到茵体总蛋白的38%,占包涵体蛋白的80%以上.Western blot鉴定表明,所表达的重组蛋白能被抗组氨酸单抗、抗PPRV标准阳性羊血清及抗PPRV疫苗的羊血清所识别,具有良好的免疫原性.