生猪乙型脑炎抗体消长规律及蚊子携带乙脑病毒调查

Study on the growth and decline of maternal antibody of Japanese encephalitis B virus and investigation of mosquito carrying virus

为探寻猪场仔猪乙型脑炎抗体消长与蚊子携带乙型脑炎病毒的之间的关系,4月份选取一批约15日龄仔猪共24头,每隔20 d采血1次,至7月共采血6次,用间接ELISA方法检测血清乙型脑炎抗体,且不同时间在跟踪猪舍共捕获约3720只蚊子,用RT-PCR方法鉴定乙型脑炎病毒核酸;结果表明,该批猪乙型脑炎抗体阳性率总体呈现先下降后升高规律,阳性率先后为83.3%、66.7%、41.6%、25%、50%、91.6%,生猪体内母源抗体水平在75日龄(6月20日)达到最低,阳性率降至25%,然后呈现明显的上升趋势,115日龄(7月30日)检测阳性率高达91.6%;37份蚊子样品,JEV核酸阳性样品16份,阳性率高达43.2%,其中7月份所采集14份蚊子样品检出7份,乙型脑类病毒(JEV)阳性检出率最高达50%,表明在乙型脑炎流行季节,受蚊子携带病毒及其叮咬影响,当仔猪JEV抗体下降最低时JEV易感,后期感染抗体升高。

To investigate the link between the dynamical changes of JEV in piglets and JEV in mosquitos. Twenty - four 15 - day old piglets were selected and blood samples were collected 6 times every 20 days. Then, we used indirect EL/SA method to detect serum antibody against JEV. At the same time, a total of 3720 mosquitos were trapped, and Japanese encephalitis virus nucleic acid was detected by RT - PCR. Results showed that the positive rate of antibody against Japanese encephalitis Bwas declined at the beginning and then increased. The positive rate for 83.6%, 83.3%, 66. 7%, 41.6%, 25%, 50%, and 91.6%. The positive lowest rate was 25% in Aprilm and the highest positive rate was 91.6% in July. Of the 37 samples of mosquitos, 16 was JEV nucleic acid positive, and positive rate is as high as 43.2%. Of the 14 samples in July, 7 samples were positive, and the positive rate of JEV was 50%. These findings indicate that when mosquitoes are active in Japanese encephalitis epidemic season, the piglets haves, higher JEV antibody positive rate, suggesting a higher JEV infection rate.