摘要
为了调查天津及周边地区猪圆环病毒2型(porcine circovirus type 2,PCV2)的感染情况及其分子特征,本研究应用PCR方法对疑似PCV2感染病例开展调查,将阳性病料接种dulac细胞分离病毒,应用PCV2 ORF2基因特异性引物对分离的PCV2进行PCR扩增,克隆、测序后进行核苷酸序列同源性分析。结果显示,不同地区PCV2的阳性率为25.0%~38.1%,其中夏季的阳性率明显高于其他3个季节,达到44.0%;不同阶段猪群中,育肥猪群的PCV2阳性率最高,而哺乳母猪相对较低。经细胞分离得到24株PCV2,其ORF2序列与GenBank中PCV2序列的同源性为87.8%~99.2%,24株分离株之间的同源性为89.4%~100.0%;遗传进化分析显示,24个分离株归属于2个分支。对其中一株分离毒株(Y16155-1株)的体外增殖特性研究表明,第4代接种dulac细胞后6h即可检出PCV2核酸,72h病毒含量达到高峰,病毒滴度为10-4.3 TCID50/0.2mL。本试验结果为进一步研究该地区PCV2分子流行病学及相关疾病的免疫防控奠定了基础。
In order to investigate porcine circovirus type 2(PCV2)infection and molecular biological characteristics from pig farms in Tianjin and its surrounding areas,the PCR method was used to investigate clinically suspected PCV2 infection case and isolate PCV2 using dulac cells,and the ORF 2 gene of PCV2 were cloning,sequencing,and comparing with ORF 2 gene of the PCV2 reference strains published in GenBank.The results showed that the positive rate of PCV2 was 25.0%to 38.1%in different regions,the positive rate in summer was obviously higher than that in the other three seasen,reaching 44.0%,and the positive rate of fattening pig was the highest,while that of milking sows was the lowest among different ages pigs.24 strains PCV2 were isolated successfully,the homology of ORF2 sequence was 87.8%to 99.2%with the reference strains,and the homology of 24 isolates strains was 89.4%to 100.0%.The phylogenetic tree analysis showed that 24 isolates belong to two branches.Propagation characteristics of a PCV2 isolate(the Y16155-1 strain)in vitro showed that the virus DNA could be detected at 6 h post inoculation and its numbers reached peak at 72 h post inoculation,the viral titer was 10-4.3 TCID 50/0.2 mL.This result laid a theoretical and scientific foundation for further study molecular epidemiology of PCV2 and the prevention and control of porcine circovirus related diseases in this area.
作者
王利丽
路超
任卫科
韩伟
李富强
郑丽
鄢明华
WANG Lili;LU Chao;REN Weike;HAN Wei;LI Fuqiang;ZHENG Li;YAN Minghua(Tianjin Animal Husbandry and Veterinary Research Institute,Tianjin 300381,China;Tianjin Engineering Research Center for Livestock and Poultry Health Breeding,Tianjin 300381,China;Tianjin Xiqing District Township Animal Husbandry and Veterinary Medicine Station,Tianjin 300380,China)
出处
《中国畜牧兽医》
CAS
北大核心
2018年第4期1027-1034,共8页
China Animal Husbandry & Veterinary Medicine
基金
天津市农业科学院院长基金(15009)
天津市农业科学院院长基金(16014)
天津市生猪产业技术体系猪病防控岗位项目(ITTPRS2017003)
天津市科技计划项目(16YFNZNC00040)
