2013-2016年广西沿海养殖凡纳滨对虾2种病毒的流行情况调查

Epidemiology of Two Viruses in Cultural Penaeus vannamei from Guangxi Coastal Areas from 2013 to 2016

【目的】对2013-2016年广西沿海养殖凡纳滨对虾2种病毒(WSSV和IHHNV)的感染情况进行调查研究,为制定广西凡纳滨对虾WSSV和IHHNV的综合防治措施提供参考。【方法】依据广西沿海凡纳滨对虾养殖现状,分别在钦州市、防城港市和北海市设立监测区,每个监测区设立15~25个采样点,2013-2016年于每年5-9月进行4~5次采样,采用国家标准方法对各监测区凡纳滨对虾的虾苗和中成虾进行2种病毒携带情况调查分析。【结果】2013年检测样品317份,WSSV和IHHNV阳性率分别为19.2%和37.9%;2014年检测样品145份,WSSV和IHHNV阳性率分别为13.8%和2.1%;2015年检测样品138份,WSSV和IHHNV阳性率分别为21.0%和2.2%;2016年检测样品88份,WSSV和IHHNV阳性率分别为21.6%和0。2013-2016年各年度之间广西沿海凡纳滨对虾WSSV的阳性率无显著差异。2013、2015及2016年钦州WSSV阳性率最高,2014年北海WSSV阳性率最高。4年间,虾苗WSSV阳性率显著小于中成虾阳性率。2013-2016年广西沿海凡纳滨对虾IHHNV阳性率呈显著下降趋势,虾苗IHHNV阳性率显著小于中成虾阳性率。2013年钦州IHHNV阳性率最高,2014-2015年北海IHHNV阳性率最高,2016年3个监测区IHHNV检测均为阴性。2013-2016年,WSSV和IHHNV混合感染的样品数量呈逐年减少趋势。【结论】2013-2016年,WSSV在广西凡纳滨对虾主要养殖区依然有不同程度的流行,虾苗WSSV阳性率显著小于中成虾阳性率;IHHNV阳性率呈逐年下降趋势,虾苗阳性率也显著小于中成虾阳性率。

[Objective]To offer a reference for comprehensive controlling of WSSV and IHHNV in cultural Penaeus vannamei in Guangxi, the epidemiology status of these viruses was investigated in Guangxi coastal areas from 2013 to 2016 in the present study. [Method] According to the current situation of P.vannamei cultivation in Guangxi coastal areas, a detection zone was set up in Qinzhou, Fangchenggang and Beihai city, respectively. There were around 15 to 25 sampling sites in each detection zone. During 2013-2016, the P.vannamei samples were collected for four to five times from May to September each year. The epidemiology status of the viruses in the adult and juvenile shrimps of each detection zone was analyzed by National standard methods. [Result] In 2013 there were 317 shrimp samples detected, in which the WSSV and IHHNV positive rates were 19.2 % and 37.9 % , respectively. In 2014, 145 shrimp samples were detected and the WSSV and IHHNV positive rates were 13.8 % and 2.1% , respectively. In 2015, 138 samples were detected and the WSSV and IHHNV positiverates were 21.0 % and 2.2 % , respectively. In 2016, 88 samples were detected and the WSSV and IHHNV positive rates were 21.6 % and 0, respectively. There was no significant difference among the annual WSSV positive rates of P.vannamei in Guangxi coastal areas during 2013-2016. The WSSV positive rates in Qinzhou were higher than those in the other two detection zones in 2013, 2015 and 2016. In 2014, and the WSSV positive rate in Beihai was the largest one among the detection zones. During the four years, there were higher infected rates of WSSV in adult shrimps than in juvenile. The IHHNV positive rates of P.vannamei in Guangxi coastal areas decreased markedly from 2013 to 2016, and there were less infected rates of IHHNV in juvenile shrimps than in the adult ones. The IHHNV positive rate in Qinzhou topped the three detection zones in 2013, and the ones in Beihai were the highest in 2014 and 2015. In 2016 the detection results were all negative in the three detection zones. From 2013 to 2016, the cases of mixed infection of two viruses declined year by year. [Conclusion] During 2013-2016 there was prevalence of WSSV infection to different extent in major P.vannanvei production areas of Guangxi, where there were lower infected rates of WSSV in juvenile shrimps than in adult ones. The IHHNV infected rates decreased year by year. And the IHHNV positive rates of juvenile shrimps were also significantly smaller than the ones of the adult shrimps.