高致病性猪繁殖与呼吸综合征病毒TJ株的分离与鉴定   总被引：1，自引：0，他引：1  

冷雪  温永俊  齐巧玲  李真光  武华 《吉林农业大学学报》2008,30(6)

从某猪场发生高热死亡的仔猪病料中分离到1株病毒,该病毒在Marc-145细胞上增殖致细胞病变。经RT—PCR检测证明该分离株为美洲型猪繁殖与呼吸综合征病毒（PRRSV）。该毒株回归易感动物可产生明显的临床症状,并引起死亡,将其命名为PRRSV TJ毒株。对其Nsp2序列进行扩增测序,结果表明：与美洲标准毒株VR-2332相比,TJ株Nsp2序列缺失第481位和第532～560位氨基酸,二者核苷酸同源性为83．7％,其编码的氨基酸同源性为77．9％。本试验结果表明,该分离株为发生了变异的PRILSV,对猪具有高致病性。  相似文献   

A quantitative assessment of the validity of animal-health surveys using stochastic modelling     

Audigé L  Beckett S 《Preventive veterinary medicine》1999,38(4):60-276

This paper presents a stochastic simulation model to evaluate the efficacy of regional or national surveys aimed at identifying infection in populations of animals. The process of evaluation involves specification or calculation of cluster-level test sensitivity and specificity, which are derived from two probability distributions of the number of individual-level positive tests expected from non-infected and infected clusters, respectively. Probability distributions for the number of positive clusters expected in a situation of freedom from infection and under various levels of cluster prevalence are specified and used to determine survey properties (the survey being considered a diagnostic system), and ROC curves are drawn. Likelihood ratios allow investigators to state the extent to which a survey result is more likely to be observed if the region or country is infected at a given prevalence than if it is free from infection. The result of a survey carried out to investigate the presence of porcine reproductive and respiratory syndrome (PRRS) in Switzerland is used to illustrate this approach. The model can be adapted to a wide range of survey designs.  相似文献   

Vaccination with a genotype 1 modified live vaccine against porcine reproductive and respiratory syndrome virus significantly reduces viremia,viral shedding and transmission of the virus in a quasi-natural experimental model     

《Veterinary microbiology》2015,175(1):7-16

The present study assessed the efficacy of vaccination against genotype 1 porcine reproductive and respiratory syndrome virus (PRRSV) in terms of reduction of the transmission. Ninety-eight 3-week-old piglets were divided in two groups: V (n = 40) and NV (n = 58) that were housed separately. V animals were vaccinated with a commercial genotype 1 PRRSV vaccine while NV were kept as controls. On day 35 post-vaccination, 14 NV pigs were separated and inoculated intranasally with 2 ml of a heterologous genotype 1 PRRSV isolate (“seeder” pigs, SP). The other V and NV animals were distributed in groups of 5 pigs each. Two days later, one SP was introduced into each pen to expose V and NV to PRRSV. Sentinel pigs were allocated in adjacent pens. Follow-up was of 21 days. All NV (30/30) became viremic after contact with SP while only 53% of V pigs were detected so (21/40, p < 0.05). Vaccination shortened viremia (12.2 ± 4 versus 3.7 ± 3.4 days in NV and V pigs, respectively, p < 0.01). The 50% survival time for becoming infected (Kaplan–Meier) for V was 21 days (CI_95% = 14.1–27.9) compared to 7 days (CI_95% = 5.2–8.7) for NV animals (p < 0.01). These differences were reflected in the R value as well: 2.78 (CI_95% = 2.13–3.43) for NV and 0.53 (CI_95% = 0.19–0.76) for V pigs (p < 0.05). All sentinel pigs (10/10) in pens adjacent to NV + SP pens got infected compared to 1/4 sentinel pigs allocated contiguous to a V + SP pen. These data show that vaccination of piglets significantly decrease parameters related to PRRSV transmission.  相似文献   

猪繁殖与呼吸综合征的抗病育种研究进展     

王晓杜  镡忠斌  王鲁彦  何珂  李开桢  潘清煜  周圻 《浙江农业学报》2014,(5)

猪繁殖与呼吸综合征(porcine reproductive and respiratory syndrome,PRRS)是近期危害养猪业最重要的疾病之一。培育抗病性品种是该病综合防治的一个有效方法。文章围绕该病抗病育种候选基因研究的主要进展进行综述,内容涉及病毒特异性受体基因、先天性免疫相关基因、抗原递呈信号通路相关基因、胞内miRNA等,并重点就今后PRRSV疾病耐受性和提高适应性免疫应答能力的研究进行展望。  相似文献   

新疆南疆一起猪繁殖与呼吸综合征的诊断     

刘永宏  赵丽  焦海宏  廖秋萍  党娜娜 《塔里木大学学报》2014,26(3):16-19

为了明确新疆南疆某猪场猪一起疫情发病原因,本研究采用发病情况调查、临床症状检查、病理学剖检、病理组织学观察和RT-PCR方法进行系统分析。结果诊断为该猪场猪感染猪繁殖与呼吸综合征病毒,且初步鉴定为高致病性猪繁殖与呼吸综合征。该诊断结果为该场乃至新疆南疆猪病的诊断和防制提供一定的方法和指导意义。  相似文献   

猪蓝耳病和猪瘟疫苗免疫后抗体检测分析     

卢会鹏  王晓珊  李艳云  郭杨柳  吴楠  史秋梅  刘铮铸  张艳英  高光平 《农业科学与技术》2014,(10):1741-1743

[目的]仔猪在14日龄接种蓝耳病毒疫苗,25日龄接种猪瘟疫苗,检测接种蓝耳病疫苗和猪瘟疫苗后的免疫合格率。[方法]采用猪繁殖与呼吸综合征病毒和猪瘟病毒ELISA抗体检测试剂盒检测抗体表达量。[结果]猪蓝耳病疫苗免疫3 d后,6.7%免疫个体为抗体阳性,免疫7 d后,26.7%免疫个体为抗体阳性,免疫14 d后,85%免疫个体为抗体阳性,免疫后30 d 100%免疫个体为抗体阳性;猪瘟疫苗免疫3 d后,13%免疫个体为抗体阳性,免疫7 d后,40%免疫个体为抗体阳性,免疫14 d后,58.3%免疫个体为抗体阳性,免疫30 d后,83.3%免疫个体为抗体阳性。[结论]仔猪在蓝耳病疫苗免疫3 d后抗体效价最低,30 d后免疫效果很好,接种猪瘟疫苗3 d后抗体效价最低,仔猪不足以抵抗病毒侵袭,虽然蓝耳病疫苗和猪瘟疫苗接种后30 d,抗体水平都达到了农业部规定的70%的标准,但是猪瘟疫苗免疫效果不能达到100%理想效果。  相似文献   

间接酶联免疫吸附试验检测猪生殖与呼吸系统综合征血清抗体的研究   总被引：2，自引：0，他引：2  

罗长保  孙颖杰 《中国兽医杂志》1997,23(10):6-7

本研究建立了检测猪生殖与呼吸系统综合征（ＰＲＲＳ）血清抗体的间接酶联免疫吸附试验（ＥＬＩＳＡ），其抗原包被浓度为２μｇ／ｍｌ，血清最适稀释度为１∶１００。试验结果表明：ＥＬＩＳＡ的敏感性高于间接免疫荧光抗体试验（ＩＦＡ），是一种切实可行的诊断方法。  相似文献   

对杭州地区4种猪病的血清学调查分析   总被引：7，自引：0，他引：7  

杨宗照  蒋建一  母安雄  陶益  陈玉华  谷根林  马有智 《浙江农业科学》2005,(3):227-229

通过对于杭州地区规模化猪场PRRS、PCV2、PR、SF等4种疾病抗体的血清学检测,发现PRRS、PCV2、PR感染率依次降低,PR的野毒感染率31.2%,总抗体阳性率为68%,猪瘟的免疫保护率为74%;下半年与上半年相比,PRRS稍有升高,SF免疫合格率有所下降,PR免疫转阳率下降,感染率稍有升高,表明防疫形势不容乐观.PRRS已经有大部分场次(93%)发生,75%的场次存在PCV2感染,7%的场次感染PR,6.4%的场次猪瘟免疫抗体不合格.建议继续做好PR、SF的免疫预防,完善PRRS疫苗,加强PCV2疫苗的研制.  相似文献   

三种猪繁殖与呼吸综合征疫苗免疫效果评价   总被引：2，自引：0，他引：2  

王建  齐新永  李凯航  葛菲菲  刘佩红  袁世山 《动物医学进展》2012,33(4):107-113

为研究不同猪繁殖与呼吸综合征病毒(PRRSV)疫苗的的免疫特性,分别采用PRRSV变异株(JXA1-R)弱毒疫苗、经典PRRSV(VR 2332)弱毒疫苗、变异株(JXA1)灭活疫苗,免疫接种PRRSV抗原和抗体阴性的健康断奶仔猪,免疫接种后70d用PRRSV变异株强毒攻毒,ELISA检测血清中PRRSV特异的抗体水平及IFN-γ、IL 2、IL 4、IL 8、IL 10的水平,并进行临床症状和肺部病理组织学观察和评分。结果表明,VR 2332、JXA1-R弱毒疫苗对免疫猪攻毒保护效果差异不显著,均为63.6%(7/11),JXA1灭活疫苗免疫攻毒保护效果较差,为36.4%(4/11)。试验还发现病毒感染猪血清中细胞因子IFN-γ和IL-10的比值可以作为评价疫苗免疫效果的一个指标。  相似文献   

Analysis of the risk of introduction and spread of porcine reproductive and respiratory syndrome virus through importation of raw pigmeat into New Zealand     

EJ Neumann  RS Morris  M Sujau 《New Zealand veterinary journal》2013,61(6):326-336

AIMS: To determine the frequency with which porcine reproductive and respiratory syndrome (PRRS) virus (PRRSv) would become established in a non-commercial pig herd in New Zealand due to illegal feeding of uncooked food waste containing virus-contaminated pigmeat. To determine the likelihood of a single incursion resulting in a multi-farm outbreak of the disease, and describe the spatio-temporal characteristics of such an outbreak.

METHODS: A Monte Carlo simulation model was constructed to determine the expected annual frequency of PRRSv infection being initiated in a non-commercial pig herd as a result of inadvertent feeding of pigmeat imported from countries endemically infected with the disease. Once the likelihood of PRRSv becoming established in a single pig herd was determined, stochastic spatially explicit infectious disease modelling software was utilised to model the temporal and spatial characteristics of the resulting epidemic.

RESULTS: Assuming the proportion of imported pigmeat remained at current levels, consumption patterns of pigmeat in households in New Zealand remained steady, and limited compliance with recently reintroduced regulations to prevent feeding of uncooked food waste, at least 4.3 pig herds per year were predicted to become infected with PRRSv. Simulation modelling of PRRSv epidemics related to initial infection of a non-commercial farm produced an estimate that 36% of these incursions would spread from the initial herd, and that these outbreaks would involve 93 herds on average in the first year. By increasing the estimated persistence of PRRSv infection in small herds, an average of 205 herds became infected in the first year.

CONCLUSIONS: Given a mean of 4.3 infected premises per year and a 36% probability of infection spreading beyond the initial infected herd, there was a 95% likelihood of a multi-farm PRRS outbreak occurring within 3 years.

CLINICAL RELEVANCE: Introduction of PRRSv through importation of virus-contaminated pigmeat presents a high risk for establishment of the disease in the pig industry in New Zealand.  相似文献