Abstract: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℃
