Embryonic development of rock bream Oplegnathus fasciatus cultured in South China Sea

This paper reported the embryonic development of rock bream Oplegnathus fasciatus which was cultured in South China Sea, China. Eggs were fertilized and incubated in a bucket at (25.640.77)℃ and salinity (S) 30~32. The diameter of fertilized eggs and lipid drops were (0.8600.023) mm (MeanSD) and (0.1910.009) mm, respectively. Twenty-two hours and 30 minutes after the fertilization, larvae were hatched. Body length of newly hatched larvae (age: 0 d) was (1.8360.078) mm. The embryonic development schedule could be divided into nine stages which were cell division stage, blastula stage, gastrula stage, blastopore closure stage, Kupffer's vesicle formation, tail-bud stage, heart beating stage, pre-hatching stage and hatching stage. Durations of division stage, blastula stage and gastrula stage were 3h, 3h and 4h 45min, respectively. Effects of different incubation temperature on embryonic development were discussed. Itindicated that gastrula stage and period from tail-bud stage to hatching stage were clearly influenced by incubation temperature.