不同温度下凡纳滨对虾和中国明对虾对白斑综合征病毒(WSSV)耐受性比较

The Difference of Tolerance to White Spot Syndrome Virus Between Litopenaeus vannamei and Fenneropenaeus chinensis at Different Temperatures

中文关键词: 凡纳滨对虾  中国明对虾  不同温度  白斑综合征病毒(WSSV)  耐受性

英文关键词: Litopenaeus vannamei  Fenneropenaeus chinensis  Different temperatures  White spot syndrome virus (WSSV)  Tolerance

中文摘要:

      本研究分别对凡纳滨对虾“壬海1号”(Litopenaeus vannamei “Renhai No.1”)和中国明对虾“黄海2号”(Fenneropenaeus chinensis “Huanghai No.2”)在3种温度条件下(24℃、28℃和32℃)，采用单尾定量口饲感染白斑综合征病毒(White spot syndrome virus, WSSV)的方法进行感染实验，比较2种对虾在不同温度情况下对WSSV的耐受性差异(L代表凡纳滨对虾，F代表中国明对虾)。结果显示，L-24℃和F-24℃组的平均存活时间分为(184.05±69.56) h和(101.68±38.45) h；L-28℃和F-28℃组的平均存活时间分别为(100.25±26.79) h和(73.38±22.22) h，相同温度组内均存在显著性差异(P<0.05)；截至第15天，L-32℃和F-32℃组的存活率分别为45.74%和23.47%。3个温度组对虾在50%的死亡率时的存活时间分别为178 h和98 h、98 h和74 h、292 h和78 h；死亡高峰时间分别为第5天和第4天、第5天和第4天、第10天和第4天。另外，分别在感染后的12 h、1 d、2 d、3 d、4 d、5 d、6 d、7 d、15 d共9个时间点对每组对虾进行活体取样，利用实时荧光定量RT-PCR技术对其进行病毒载量检测，从对虾体内肌肉组织病毒载量的角度探寻不同对虾抗病性能的差异。6 d时，L-24℃和F-24℃组对虾肌肉内病毒载量分别达到(2.97×106±7.44×106)和(8.08×106±3.22×106) copies/ng DNA，差异极显著(P<0.01)，L-28℃和F-28℃组分别达到(6.73×106±1.49×106)和(1.20×107±6.15×105) copies/ng DNA，差异极显著(P<0.01)；15 d，L-32℃和F-32℃组分别达到(5.18×103±4.32×103)和(3.78×104±8.97×103) copies/ng DNA，差异显著(P<0.05)。研究表明，2种对虾在3种温度环境下感染WSSV后，凡纳滨对虾耐受WSSV能力要高于中国明对虾；不同温度下同种对虾肌肉体内WSSV的增殖能力从强到弱依次为28℃组、24℃组和32℃组。

英文摘要:

      The present study evaluated the effects of white spot syndrome virus (WSSV) infection in Litopenaeus vannamei ‘Renhai No.1’ and Fenneropenaeus chinensis ‘Huanghai No.2’ at various temperatures (24℃, 28℃, and 32℃) using quantitative feeding method (L represents L. vannamei, and F represents F. chinensis). The results showed that the average survival time of group L-24℃, F-24℃, L-28℃, and F-28℃ was (184.05±69.56) h, (101.68±38.45) h, (100.25±26.79) h, and (73.38±22.22) h, respectively. The survival time between two kinds of shrimps at same temperature was significantly different (P<0.05). At the 15th d, the survival rate of group L-32℃ and F-32℃ was 45.74% and 23.47%, respectively. The time of 50% mortality rate of two shrimps at three temperatures was 178 h and 98 h, 98 h and 74 h, 292 h and 78 h, respectively. The time of death peak of two shrimps among three temperatures was 5 d and 4 d, 5 d and 4 d, 10 d and 4 d, respectively. The virus loads in muscle of L-24℃ and F-24℃ at 144 h was (2.97×106±7.44×106) and (8.08×106±3.22×106) copies/ng DNA with the highly significant difference (P<0.01). The virus loads in muscle of L-28℃ and F-28℃ at 144 h was (6.73×106±1.49×106) and (1.20×107±6.15×105) copies/ng DNA with highly significant difference (P<0.01). The virus loads of muscle of L-32℃ and F-32℃ at the 15th d was (5.18×103±4.32×103) and (3.78×104±8.97×103) copies/ng DNA with a significant difference (P<0.05). These results indicates that L. vannamei are more tolerant to WSSV infection than F. chinensis, and the ability of multiplication of WSSV in muscle at different temperatures was 28℃>24℃>32℃