Salinity tolerance of embryos and yolk-sac larvae of Paralichthys olivaceus

The experimental salinity levels were designed at 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, using natural sea water (salinity 32 ), distilled water and dry salt from sea water. The water temperature was (18 ± 1 )℃. When salinity ranged from 5 to 35, the hatching rate of embryos of Paralichthys olivaceus was more than 95 % and the morphorgenesis of most of the larvae was normal. The larval survival rate was more than 95 % 72 h after hatching. Although the total length of the larvae after hatching was a little longer at lower salinity than at natural salinity, there was no significant difference in total length between the larvae within 10 ～ 35 of salinity after 72 h (P 0. 05 ). More than 50 % of the naturally hatched larvae could survive 72 h after transferred to different salinity levels ranging from 5 to 45. It comes to the conclusion that a salinity ranging from 10 to 35 is suitable for incubation of P. olivaceus, and within salinity of 5 ～45, the yolk-sac can grow normally.