国内部分地区猪场猪繁殖与呼吸综合征病毒的检测及高致病性毒株的分离与毒力鉴定  

Detection of porcine reproductive and respiratory syndrome virus on pig farms in some areas of China and isolation and pathogenicity identification of highly pathogenic strains

作　　者：沙俊舟 焦文涛 丁旭娜 段进坤 车艳杰 鲍恩东[1,2] SHA Junzhou;JIAO Wentao;DING Xuna;DUAN Jinkun;CHE Yanjie;BAO Endong(College of Veterinary Medicine,Nanjing Agricultural University,Nanjing 210095,China;Institute of Tianjin Ringpu Biological Technology Co.,Ltd.,Tianjin 300308,China)

机构地区：[1]南京农业大学动物医学院,南京江苏210095 [2]天津瑞普生物技术股份有限公司研究院,天津300308

出　　处：《畜牧与兽医》2021年第4期124-131,共8页Animal Husbandry & Veterinary Medicine

摘　　要：为了解国内部分地区猪繁殖与呼吸综合征病毒(PRRSV)的流行情况,采用国标RT-PCR方法,对2017至2019年间来自全国14个省(市)的不同规模化猪场的1441份病料进行了PRRSV检测,并对分离到的高致病性PRRSV(HP-PRRSV)毒株进行了分子特性和致病特性研究。结果表明,猪场PRRSV阳性率为22.14%,其中HP-PRRSV占到了阳性样品的49.84%;筛选部分病料分别接种猪肺泡巨噬细胞(PAM)和Marc-145细胞,成功分离到1株病毒,经电镜观察和间接免疫荧光试验(IFA)鉴定为PRRSV,并命名为RP19。对RP19毒株nsp2和ORF5基因序列分析表明,RP19与高致病性毒株TJ的序列相似度最高,并且其nsp2基因编码区含有特征性的(29+1)个氨基酸缺失。以10^(5.0) TCID_(50)/mL的攻毒剂量在5周龄的仔猪上进行动物回归试验。结果显示,与对照组相比,RP19的攻毒组仔猪的日增重显著减少,体温升高,出现咳嗽、身体颤抖以及后肢麻痹等严重的临床症状,且有1头仔猪出现死亡,说明RP19有较强毒力。病理组织学结果显示,病猪肺脏呈现PRRSV感染造成的典型弥漫性间质性肺炎症状。本研究调查了近年来PRRSV在我国14省(市)的流行情况,并分离到1株高致病性毒株,为PRRS的预防和疫苗制备提供了依据。To investigate the epidemic trend of porcine reproductive and respiratory syndrome virus(PRRSV)in some areas of China,1441 samples of PRRSV from different large-scale pig farms in 14 provinces and cities of China from 2017 to 2019 were collected and detected by RT-PCR according to the national standard.Further studies were conducted on one isolated pathogenic strain.The results showed that the positive rate of PRRSV in pig farms was 22.14%,and HP-PRRSV accounted for 49.84% of the positive samples.A number of samples were used to isolate viruses using porcine alveolar macrophages(PAM)and Marc-145 cells respectively,and one virus strain was successfully isolated and identified as PRRSV by electron microscopy(EM)and indirect immunofluorescence assay(IFA),and was named RP19 sequence analysis of the nsp2 and ORF5 genes of the RP19 strain showed that it had the highest sequence similarity to the highly pathogenic PRRSV TJ strain and that the coding region of the nsp2 gene contained a characteristic(29+1)amino acid deletion.The animal experiment was conducted on piglets aged 5 weeks with a challenge dose of 10^(5.0) TCID_(50)/mL.The results showed that,compared with the control group,the daily weight of the piglets in the RP19 group was significantly decreased,their body temperature was increased,and their severe clinical symptoms such as coughing,trembling and hind limb paralysis were observed.In addition,the presence of mortality in one piglet indicated that RP19 has some lethal pathogenicity.Histopathological results showed that the lungs of the piglets showed typical symptoms of diffuse interstitial pneumonia caused by PRRSV infection.This study explored the epidemic trend of PRRSV in 14 provinces and cities China in recent years,and isolated and identified a HP strain,which provided a basis for PRRS prevention and vaccine preparation.

关 键 词：猪繁殖与呼吸综合征病毒 检测 分离 致病性 猪 

分 类 号：S852.659.6[农业科学—基础兽医学]