广东省猪圆环病毒2型毒株分离 及全基因序列分析

为了解广东省猪圆环病毒2 型(PCV2）的流行、变异及进化情况，对2013 年广东省多个猪场发生PCV2 感染的病猪血清进行PCV2 病毒分离，参考GanBank 上已发表的PCV2 全基因序列，设计3 对引物，用PCR 方法扩 增其全基因序列，测序并进行序列分析。结果分离到9 株PCV2 毒株，全基因序列长度都为1 767 bp。同源性分析表 明，9 株PCV2 分离株核苷酸同源性为93.6%~99.4%，与2012 年分离株同源性为94.5%~99.7%，与2011 年分离株同 源性为94.2%~99.7%，与GenBank 中其他PCV2 分离株的同源性为93.2%~99.7%。9 株PCV2 的ORF2 核苷酸及其推 导的氨基酸序列同源性分别为89.0%~99.9%和86.4%~100%，存在一定的变异。基因型分析表明，有5 株属于 PCV2d，3 株属于PCV2b，1 株属于PCV2a。对2011要2013 年分离的PCV2 基因组特征进行分析，发现PCV2 核苷酸序 列比较稳定，与世界其他分离株也具有较高的同源性。

Isolation and sequence analysis of PCV2 strains from Guangdong province

In order to know the epidemic, variation and evolution of PCV2 in Guangdong province, serum samples from suspected pigs infected PCV2 in many farms of Guangdong province were used to isolate PCV2. According to the sequence of PCV2 published in GenBank, 3 pairs of primers were designed and amplified by PCR. The results showed that each of 9 genomes showed 1 767 bp in length. The homology of 9 isolates was 93.6%~99.4%, while the homology with isolates in 2012 was 94.5%~99.7%, the homology with isolates in 2011 was 94.2%~99.7%, and the homology with other isolates in GenBank was 93.2%~99.7%. The ORF2 of the 9 isolates had 89.0%~99.9% nucleotide sequence homology and 86.4%~100% amino acid homology. 5 isolates belonged to PCV2d genotype while 3 isolates belonged to PCV2b and 1 isolate belonged to PCV2a. The analysis of PCV2 genomic characteristics isolated from 2011 to 2013 found that the nucleotide sequence of PCV2 was stable, and the homology of these isolates were high with other isolates of the world.