虾池中桡足类及其休眠卵携带对虾白斑综合症病毒的初步调查研究

Primary Investigation on the WSSV Carrying Status in Copepoda and Their Resting Eggs in Shrimp Ponds

探讨对虾白斑综合症（White Spot Syndrome WSS）与虾池中桡足类之间的关系，于2003年5～10月份，在暴发过对虾白斑综合症的池塘中采集桡足类样品共128个，并从冬季底泥样品分离出桡足类休眠卵样品20个，以及此种休眠卵孵化得来的桡足类幼体样品5个。利用PCR斑点杂交法以及巢式PCR法检测样品中对虾白斑综合症病毒（White Spot Syndrome Virus WSSV）携带情况。结果表明，5～10月份桡足类样品中均能检测到阳性样品，总的阳性率为56．3％；其中，5月份样品阳性率为37．5％，6，8，9，10月份各取样1次，每次样品中的阳性率均在60％以上。在20例桡足类休眠卵样品中有1例为阳性，阳性率为5％；并且实验室中孵化此种休眠卵得来的桡足类幼体样品中检测到阳性，阳性率为40％。本研究初步表明，桡足类是WSSV的携带者或传播媒介之一，且冬季池塘底泥中携带WSSV的桡足类休眠卵可萌发出带病毒的桡足类。

The paper describes the research on the WSSV carrying status in copepoda and their resting eggs. During May to October, 2003, in Rushan shrimp farm, 128 samples of copepoda were collected from the shrimp （Fenneropenaeus chinensis） cultural ponds, where White Spot Syndrome （WSS） had taken place in 2002. In addition, 20 samples of copepoda resting eggs were separated from the pond mud in Decemeber, 2003, and 5 samples of nauplins hatched from that kind of resting eggs were detected. These samples were detected for WSSV by the method of PCR-dot-blot hybridization or nest-PCR, both of which could be used in the detection of trace WSSV. The results showed＇that the WSSV could infect the copepoda and the average positive rate of the copepoda samples reached 56.3 %. The positive rate in May was 37.5 % and in July, August, September and October it was more than 60 %. Furthermore, one positive case was detected from the copeopda resting eggs samples and two positive cases in the nauplins hatched from this kind of resting eggs. The results indicated that copepoda was one of the vectors of WSSV, and it was extremely possible that copepoda resting eggs carrying WSSV hatch, new WSSV carrying copepoda the next year.