高致病性PRRSV的分离及其Nsp2和ORF5基因的序列分析  

Isolation of highly pathogenic porcine reproductive and respiratory syndrome virus and sequence analysis of its Nsp2 and ORF5 genes

作　　者：马静云[1] 李浩波[1] 王玲玲[1] 何晓明[1] 王连想[1] 谢青梅[1] 毕英佐[1] 

机构地区：[1]华南农业大学动物科学学院,广东广州510642

出　　处：《中国兽医科学》2008年第8期650-657,共8页Chinese Veterinary Science

基　　金：广东省重大科技专项(2005A20902001)

摘　　要：从广东省不同地区疑似高致病性猪生殖与呼吸综合征病料中分离出能引起Marc-145细胞病变的病毒，经RT-PCR检测，确定分离物中存在美洲型猪生殖与呼吸综合征病毒（PRRSV），将此细胞病毒液命名为GDBl，用其感染回归5头40日龄健康仔猪，采集发病及死亡猪组织，重新用Marc-145细胞进行病毒分离，将再次分离到的病毒命名为GDB1F。对GDB1、GDBIF的Nsp2、ORF5基因序列进行测定分析。结果表明，单独感染猪2／2发病死亡，同居感染的3头猪全部发病，2头死亡；感染后2～4d所有感染猪均出现体温升高。死亡猪表现为严重的出血性、间质性肺炎，肢体远端皮表出血。序列分析结果表明，GDB1和GDB1F株的Nsp2基因与国内高致病性PRRSV分离株JXA1、HN2Nsp2、HNXT1、HNyz、HUB2、HUN1的同源性很高，达98．4％～99．0％。GDB1和GDB1F株的ORF5基因存在部分突变，没有缺失，与国内高致病性PRRSV分离株JXA1、HUB2、JX0612、GDZC1的同源性高达97．5％～99．8％。A strain of virus causing CPE of Marc-145 cell lines was isolated from samples of dead pigs with highly pathogenic porcine reproductive and respiratory syndrome in different areas of Guangdong Province. The virus was identified to be porcine reproductive and respiratory syndrome virus（PRRSV） by RT-PCR,which was designed GDB1. Five 40-day-old healthy piglets were infected with GDB1. Another strain of virus was isolated from the infected pigs by Marc-145 cell lines,and the Nsp2 and ORF5 genes of GDBland GDB1F were cloned and sequenced respectively. The results showed that 5/5 pigs infected with PRRSV had classical symptoms,and 4/5 died. All the infected piglets＇ body temperature raised on day 2 to 4 post-infection. Interstitial pneumonia, carnification and haemorrhage existed in the lungs of all the died piglets. Sequencing results showed that Nsp2 genes of GDB1 and GDB1F strain shared 98.4% to 99.0% homologies with those of JXA1, HN2 Nsp2, HNXT1, HNyz, HUB2 and HUN1 strains. ORF5 genes had a few mutation but no deletion,and shared 97. 5% to 99. 8% homologies compared with those of JXA1, HUB2 ,JX0612, GDZC1.

关 键 词：高致病性猪生殖与呼吸综合征病毒 分离 NSP2基因 ORF5基因 序列分析 

分 类 号：S852.659.6[农业科学—基础兽医学] Q522.6[农业科学—兽医学]