Abstract: The complete genome sequences of 42 PRRSV strains derived from Guangdong and completerecombination events occurred in the parental strain of JXA1?R?CN?2009 from 2010 to 2018. Vaccine strains Ingelvac ATP?US?2006 and CH?1R?CN?2008 appeared as secondary parental strains in event 10，the recombinant strain of this event was Guangdong strain isolated from 2018. Recombination between vaccine strains can be seen in events 18，25， but the software also shows that this event may have evolved naturally rather than recombined. This paper has certain significance for the scientific and standardized use of modified live vaccines in Guangdong pig farms. sequences of 6 PRRSV vaccine strains were selected from all 424 PRRSV complete sequences available on GenBank database to carry out recombination analysis using RDP4(Recombination detecting program 4，RDP4) software. Recombination events between Guangdong strains were found to be concentrated in 2010，2011 and 2015. 12

Key words: Guangdong PRRSV strain； Vaccine strain； Recombination analysis

摘要： 从GenBank上可查的全部424株猪繁殖与呼吸综合征病毒（Porcine reproductive and respiratory syndrome virus，PRRSV）全基因序列中筛选出了42株来源于广东的PRRSV毒株全基 因组序列与6株PRRSV疫苗株全基因序列，用RDP4(Recombination detecting program 4，RDP4) 软件进行重组分析。发现广东株之间的重组事件集中在2010年、2011年和2015年。JXA1?R? CN?2009作为亲本毒株出现在12个重组事件中，重组体的年份从2010年延续到2018年。疫苗 株Ingelvac ATP?US?2006与CH?1R?CN?2008作为次要亲本毒株出现在事件10中，该事件的重组 体为广东2018年的毒株。在事件18和25中可以见到疫苗株之间的重组，但软件同时显示该 事件可能是自然进化而非重组。该研究对广东猪场科学规范的使用弱毒疫苗有着一定指导意 义。

关键词: 广东PRRSV毒株； 疫苗株； 重组分析