猪圆环病毒病的临床表现及其防治措施

猪圆环病毒有2个血清型,即PCV-1和PCV-2,其中PCV-1对猪无致病性,而PCV-2对猪的致病性较强。自1991年我国猪场首次报道有猪圆环病毒病（PCV-2）存在以来,该病已在全国各地猪场迅速蔓延。据不完全统计,目前我国猪场的PCV-2隐性感染率达42．9％,个别地区猪场感染率达100％,给我国养猪业造成了较大经...     

某猪场“僵猪”致病原因分析

为分析某猪场出现"僵猪"的可能原因,对该猪场的11头"僵猪"采集血液样品,用RT-PCR方法检测猪瘟病毒(CSFV)和猪繁殖与呼吸综合征病毒(PRRSV),用PCR方法检测猪伪狂犬病毒(PRV)和猪圆环病毒2型(PCV-2)。结果11份样品的CSFV、PRRSV及PRV检测均为阴性,PCV-2经套式PCR检测均为阳性。对11份样品分离血清,应用酶联免疫吸附试验(ELISA)检测PCV-2血清抗体,结果均为阳性。随后又对与11头"僵猪"同舍的部分健康猪进行了上述4种病毒的RT-PCR及PCR检测,结果均为阴性。由此推测PCV-2极有可能是该猪场形成"僵猪"的主要因素之一。     

某规模化猪场猪繁殖障碍性疫病ELISA及六重PCR的检测分析

为了解贵州省某规模化猪场6种繁殖障碍性疫病的感染状况,试验采用ELISA试剂盒对送检的血清样品进行了猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒(PCV-2)、猪乙型脑炎病毒(JEV)、猪伪狂犬病毒(PRV)和猪细小病毒(PPV)抗体水平的检测,同时对送检的组织病料进行六重PCR检测。结果表明:CSFV、PRRSV、PCV-2、JEV、PRV和PPV的抗体阳性率分别为93.2%、52.7%、49.4%、83.8%、87.3%和78.8%,其中PRRSV免疫效果较差;另外,该猪场未免疫PCV-2疫苗,但是其抗体阳性率相当高,血清学检测结果显示,该猪场很可能存在PRRSV和PCV-2感染;送检的组织病料经六重PCR检测结果显示,该猪场存在PRRSV和PCV-2野毒感染。说明该猪场应加强猪繁殖与呼吸综合征和猪圆环病毒病的预防工作。     

华东地区PMWS患病猪群PCV-2的检测及其基因特征

用 PCR方法 ,对江苏、上海、山东、江西、安徽和浙江等省市 6 5家猪场 99例断奶仔猪多系统衰弱综合征(PMWS)肺脏和淋巴结病料 ,进行了猪圆环病毒 - 2 (PCV- 2 )基因检测 ,发现其中 18家猪场 2 1例病料为 PCV- 2阳性。源自安徽和上海的 PCV- 2分离株经基因序列分析显示 ,2个分离株部分 ORF2 与国外分离毒株同源性为 92 %～99%。安徽分离株 AHHF6与韩国分离株 KSY- 1同源性为 99% ,而上海分离株 SHHT1与加拿大分离株 Imp.114 7同源性为 98%。上述结果表明 ,我国 PMWS患病猪群广泛存在 PCV- 2 ,不同地区 PCV- 2存在一定基因差异 ,它们可能来源于不同国家或地区     

湖北省部分猪场猪"红斑病"主要病因的调查

自2001年以来,湖北部分猪场断奶仔猪出现不明原因的红斑症状并伴随高热现象,病死率高达60%。为了探索其主要致病因素,对来源于22个发病猪场的108份病料进行实验室诊断。结果108份病料中猪圆环病毒2型(PCV-2)、猪繁殖与呼吸综合征病毒(PRRSV)、猪瘟病毒(CSFV)、猪附红细胞体(E.suis)和猪弓形虫的检出率分别为83.3%、33.3%、22.2%、48.1%和14.8%;同时存在PCV-2、PRRSV和E.suis等不同程度的混合感染现象,其中PCV-2和E.suis混合感染最为严重,阳性率达32.4%。表明湖北省部分"红斑病"发病猪场均不同程度存在PCV-2、PRRSV和附红细胞体感染的现象,特别是PCV-2感染情况极为严重,提示PCV-2等免疫抑制性疾病可能是湖北省一些猪场出现红斑症状的主要原因。     

安徽省仔猪腹泻5种病毒感染情况的调查研究

为了解安徽地区仔猪病毒性腹泻流行病学特点,对从安徽省37个规模化猪场采集腹泻仔猪的粪便或病死猪肠段共计186份,用RT-PCR和PCR技术进行了猪流行性腹泻病毒(PEDV)、猪传染性胃肠炎病毒(TGEV)、轮状病毒(RV)、猪伪狂犬病病毒(PRV)、猪圆环病毒2型(PCV-2)等5种病毒的检测.结果表明,PEDV阳性病料数占59.1％,阳性猪场占75.7％;TGEV阳性病料数占5.4％,阳性猪场占8.1％;RV阳性病料数占2.7％,阳性猪场占2.7％;PRV阳性病料数占8.1％,阳性猪场占21.6％;PCV-2阳性病料数占25.8％,阳性猪场占54.1％.PEDV与TGEV混合感染占4.3％,PEDV与PCV-2混合感染占18.8％,PEDV与PRV混合感染占10.8％,PRV和PCV-2混合感染占4.8％;其他病因50例,占26.9％.结果表明,PEDV、PCV-2 、PRV的单纯或混合性感染是近年安徽省仔猪腹泻的最为重要的3种病毒性病因,说明在今后的仔猪腹泻病防控过程中,应该着重加强对该3种疾病的综合防控.     

广东省猪PCV-2感染的病原学调查

2004年-2006年从广东省4个不同地区458个规模化猪场采集2128份病料,进行了PCV-2的抗原检测,结果表明,被检地区的猪群中普遍存在PCV-2感染,检测的458个规模化猪场中有372个猪场有PCV-2阳性猪,平均阳性率达到81．22%;2128份被检病料样品中有863份为阳性,平均阳性率达40．55％（863／2128）;不同地区不同时段猪场阳性率为63．64％～92．86％,病料样品的阳性率为24．00%～48．00％。     

一株2型猪圆环病毒的分离及其序列、致病性的初步分析

断奶仔猪多系统衰竭综合征(Postweaning multi-system ic wasting syndrome,PMWS)是由2型猪圆环病毒(Porcine circovirustype 2,PCV-2)引起的一种传染病。2006年,黑龙江省某猪场饲养的128头仔猪中,有80%的仔猪患有先天性震颤、吃奶困难,采集死亡与患病仔猪的病料经PCR鉴定,结果     

PCR技术在猪圆环病毒2型检测中的应用

参照Gen Bank中已发表的猪圆环病毒2型(PCV-2)ORF2基因序列,设计合成1对引物,建立了检测猪场疑似病例临床样本中PCV-2的PCR方法。结果显示,PCV-2的ORF2扩增产物经琼脂糖凝胶电泳,呈现1条630 bp的特异性条带,与预期目的片段大小一致。应用该方法对安徽省3个猪场的30份病料进行了PCV-2检测,结果有9份检测出PCV-2,阳性率为30%。结果表明,该试验建立的PCR方法,是一种快速、灵敏、高效的PCV-2检测技术。     

猪圆环病毒2型LN株初步分离与全基因组测序

为了解猪圆环病毒2型(PCV-2)在河南地区猪场的流行情况,采用常规方法对采集自河南省洛阳市某猪场病料中的PCV-2进行了分离,并对其全基因组进行了扩增、克隆和测序。结果表明,从患病仔猪的病料中分离到了1株PCV-2,命名为LN株,该毒株的全基因组序列大小为1 767 bp。该试验结果为从分子水平上揭示PCV-2的致病特性,开发PCV-2的相关疫苗和诊断产品奠定了基础。     

Porcine circovirus type 2 infection before and during an outbreak of postweaning multisystemic wasting syndrome on a pig farm in the UK

The presence of porcine circovirus type 2 (PCV-2) and other pathogens before and during an outbreak of postweaning multisystemic wasting syndrome (PWMS) in pigs is evaluated in this study. At the time of the outbreak on a large commercial pig farm in the UK, serum samples and data were collected in two independent on-going research projects, one in weaned pigs and the other in sows. Serum samples of growing pigs and sows were PCV-2-antibody and PCR positive before and during the PMWS outbreak. Upon sequencing, PCV-2 isolates collected before the outbreak were identified as PCV-2a, and isolates collected during the outbreak were identified as PCV-2b, suggesting a shift of PCV-2 genotypes present on the farm. Pigs in the weaner study were from sows originating from different breeders and an association of sow origin and PCV-2 serostatus in offspring was found. Further, pigs had higher odds to be PCV-2 antigen positive if the sow was PCV-2 antibody positive around farrowing, the sow was of higher parity, and were less likely to test antigen positive if the sow was sourced from a particular breeder. The findings of this study highlight the potential role of the immune status of the sow on the occurrence of PMWS.     

华南地区猪圆环病毒和猪繁殖与呼吸综合征病毒检测分析

为了解华南地区猪圆环病毒及猪繁殖与呼吸综合征病毒的最新流行情况,采集了华南地区11个规模猪场各饲养阶段猪血清807份,用套式PCR(nPCR)检测猪圆环病毒1型(PCV-1)和猪圆环病毒2型(PCV-2);采集了若干猪场2010年1月至2011年8月期间有咳嗽、喘气、消瘦及疑似PDNS等临床症状的猪血清312份,以及无临床症状猪血清104份,以nPCR检测PCV-2,以一步法反转录PCR(RT-PCR)检测猪繁殖与呼吸综合征病毒。结果发现,所调查的11个规模猪场中只有5个检出PCV-1,所有猪场均检出PCV-2。PCV-2阳性率为30.61%,而PCV-1阳性率仅为4.21%;经产母猪和7周龄以上保育猪PCV阳性率最高;有临床症状的猪血清PCV-2阳性率为58.65%,PRRSV阳性率为37.82%,PCV-2阳性猪群中有39.89%的猪同时感染PRRSV;有症状猪群7月～9月的PCV-2感染率最高,而1月～3月最低;无临床症状猪血清PCV-2阳性率为27.9%,PRRSV阳性率为0.96%,PCV-2与PRRSV无混合感染。证明PCV尤其是PCV-2在华南地区仍广泛传播并流行,而且PCV-2与PRRSV混合感染致病情况较多。PCV-2的感染率与季节有一定的相关性,种猪带毒情况严重。     

Detection of Porcine Circovirus Type 2, Porcine Parvovirus and Porcine Pseudorabies Virus from Pigs with Postweaning Multisystemic Wasting Syndrome by Multiplex PCR

Multiplex PCR was established to detect porcine circovirus type 2 (PCV-2), porcine parvovirus (PPV) and porcine pseudorabies virus (PRV) and applied to samples from 137 piglets exhibiting clinical signs of postweaning multisystemic wasting syndrome (PMWS). PCV-2 DNA was detected from all samples. Moreover, 43 samples were positive for PPV but negative for PRV; 11 samples were positive for PRV but negative for PPV; and 35 samples were positive both for PPV and PRV. These results suggests that PCV-2 co-infection with PRV and PPV may play an important role in PMWS. Also, multiplex PCR is an appropriate candidate method for diagnosis of PCV-2, PRV and PPV simultaneously in field cases.     

猪皮炎肾病综合征组织病理学和PCR诊断

应用病理学和PCR方法,对浙江某猪场送检的疑似猪皮炎肾病综合征（PDNS）病猪进行诊断。结果发现肾脏呈现纤维蛋白性肾小球肾炎变化,真皮及皮下血管表现为坏死性脉管炎,淋巴组织中大量淋巴细胞缺失、多核巨细胞浸润,PCR扩增产物显示猪圆环病毒2型（PCV-2）阳性。结果表明,该猪场感染了PCV-2,并表现为PDNS的病理特征。     

山东种公猪精液携带主要病原的检测

采用PCR技术,对2007年-2009年山东部分地区的38个猪场和人工授精站的生产公猪精液样品727份进行了猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、伪狂犬病病毒(PRV)、猪圆环病毒2型(PCV-2)和猪细小病毒(PPV)5种主要病原的检测。结果检出CSFV、PRRSV、PRV、PCV-2和PPV的阳性数和阳性率分别为18份(2.48%)、27份(3.71%)、7份(0.96%)、33份(4.54%)、9份(1.24%),有7份样品为2种以上病原混合感染,其中以PRRSV+PCV-2混合感染最多。结果表明精液传播病毒仍是当前母猪繁殖障碍的重要原因之一,应重点加强对种公猪的疫病净化和公猪精液管理,从源头控制传染源。     

1例规模化猪场暴发高致病性繁殖与呼吸综合征（HPPRRS）与圆环Ⅱ型（PCV-2）混合感染的诊治

四川省邻水县的1个规模化猪场60-60日龄猪只430头相继暴发疲病,采集15头病猪血清样品和2头病死猪肺和脾脏组织病料,采用HPPRRSV RT—PCR试剂盒（军事兽医研究所涂长春教授惠赠）检测,结果是8份血清（占55．8％）和2份病料（100％）为阳性。同时,6份血清和2头病死猪肺和脾脏组织病料用PCV-2 PCR试剂盒（自制）检测,结果是3份血清（占50％）和2份病料（100％）为阳性;结果表明：该猪场暴发了HPPff,RSV和PCV2混合感染。     

Prevalence of infection with porcine circovirus-2 (PCV-2) and porcine reproductive and respiratory syndrome virus (PRRSV) in an integrated swine production system experiencing postweaning multisystemic wasting syndrome

The objective of this study was to evaluate the prevalence of infection with porcine circovirus-2 (PCV-2) and porcine reproductive and respiratory syndrome virus (PRRSV) through a longitudinal study in an integrated swine production system (7 farms) experiencing postweaning multisystemic wasting syndrome (PMWS). Risk factors for PCV-2 infection and for PCV-2 and PRRSV coinfection were also evaluated. Fifteen sows from each herd and 4 non-cross-fostered piglets from each sow were randomly selected at farrowing and ear-tagged at birth. Serum samples were analyzed for antibodies to PCV-2 and for detection of the PCV-2 and PRRSV genomes. Statistical analyses involved 2 approaches. The 1st approach characterized the dynamics of PCV-2 infection and their relationship with PRRSV infection. The 2nd approach analyzed the probability of being infected by PCV-2 or by both PCV-2 and PRRSV through a generalized linear mixed model incorporating sow and farm characteristics. At the 1st sampling time (1 wk of age), there was a significant relationship between sow PCV-2 infection and piglet PCV-2 infection (P < 0.0001). The risk of PCV-2 and PRRSV coinfection was 1.85 times greater in piglets from a sow with low titers of PCV-2 antibodies than in piglets from sows with medium to high titers (P = 0.03) and was 2.54, 2.40, and 2.02 times greater, respectively, in piglets from primiparous sows, PCV-2-infected sows, and farms in an area of high pig density than in piglets from sows of higher parity (P = 0.004), noninfected sows (P = 0.04), and farms in a low-density area (P = 0.09).     

猪圆环病毒2型PCR检测方法的建立及其在临床检测中的应用

选择猪圆环病毒2型(PCV-2)基因保守区设计1对引物P1和P2,扩增536 bp的片段,该方法可以特异地检测出PCV-2的DNA,而对猪细小病毒、猪瘟病毒、猪伪狂犬病毒及未接PCV-2的PK-15细胞均呈阴性;该法能检测出29 ng/L的病毒DNA。对扩增片段进行测序,结果表明扩增片段属于PCV-2。应用该方法对2008年度上海及周边地区送检的91份临床样本进行了PCV-2的检测,结果表明,阳性样本为52份,阳性率为57.14%。研究结果表明,建立的PCR方法检测PCV-2具有较好的敏感性和特异性,可用于PCV-2感染疑似病例的诊断及其分子流行病学调查。     

Clinical and pathological observations on pigs with postweaning multisystemic wasting syndrome

The aim of this work was to characterise the lesions and agents present in clinically normal and clinically affected pigs on a farm during an outbreak of postweaning multisystemic wasting syndrome (PMWS), and to evaluate the diagnostic techniques for detecting porcine circovirus type 2 (PCV-2) and other microorganisms. Four pigs in the early stage and 11 pigs in the late stage of the disease, and eight clinically normal pigs were necropsied. Samples of lymphoid tissue and serum were also obtained from 12 slaughter pigs from the same farm. The tissues were examined histopathologically, and in situ hybridisation, serology and PCR were used to detect porcine circovirus type 1 (PCV-1) and/or PCV-2 in tissues and/or sera. The presence of porcine reproductive and respiratory syndrome virus (PRRSV), Aujeszky's disease virus (ADV) and porcine parvovirus (PPV) were also investigated. Characteristic microscopical lesions of PMWS were observed in the lymphoid tissues of the pigs in all three necropsied groups; the lesions were most common and severe in the pigs in the early stage of the disease, less so in the pigs in the late stage of the disease, and least in the clinically normal pigs. PCV-2 infection was detected in all the necropsied pigs by in situ hybridisation and PCR. Only three pigs had the PCV-1 genome in serum or lymph node tissue. In contrast, the slaughter pigs had no microscopical lesions and no PCV-2 nucleic acid in their serum or tissues, and only one of them had the pCV-1 genome in its serum. Immunohistochemical, serological and PCR studies revealed that PRRSV and ADV were also present on the farm during the outbreak.     

青海省部分地区猪圆环病毒2型感染的血清学调查

应用猪圆环病毒2型抗体酶联免疫检测试剂盒,测定了青海省省内8个猪场的1 000个血清样本,对不同地区、不同年龄猪的进行了血清学调查.结果显示,青海省8个猪场均有猪圆环病毒2型( PCV-2)感染,全省猪的PCV-2感染的平均血清阳性率为25.9％,其中母猪、种公猪、生长育肥猪、保育猪及哺乳仔猪抗体阳性率分别35.3％、...