1.The study of hybridization and inbreeding of groupers: The purpose of this study is to investigate the availability of the hybridization of giant grouper (Epinephelus lanceolatus) and orange-spotted grouper (E. coioides). Both parental fish have been collected in early 2018. We adjusted the water temperature at 27±1°C for male giant grouper and female orange-spotted grouper. At the same time, fish were fed with
Japanese scad, mackerel, and the skipjack tuna in order to enhance the gonadal development. We performed LHRH-A2 and HCG artificial maturation experiments in May, September and October. Totally, we obtained 2542 g fish eggs and 120 ml fish milt. However, there were no successful fertilization occurred, though we raised the female fish culture temperature above 28°Cand modified the concentrations of LHRH-A2 and HCG. Since the fish sperms still showed good motility, we suspected that the failure of artificial fertilization might be due to the immaturity of the eggs.
2.Cultivation and propagation of the flounder, Paralichthys olivaceus: The temperature stimulation successfully induces spawning and fertilization of the olive flounder (P. olivaceus). The broodstock began to spawn on January 4 (average of 100-150g of eggs per day). A total of 200g fertilized eggs were collected. The fertilization rate was 40%. The fry breeding with deep seawater and surface seawater, the feeding condition and growth well (Temp. = 21±1°C). In addition, the optimum stocking density test in different breeding stages (7g and 100g). The result showed that the fish in the larvae stage(7g) stocked with the lowest stocking density (100 fish/ m2 ) resulted in best weight gain rate (596.71±6.96%). In the juvenile stage (100g) stocked with 60 fish/ m2 density in best weight gain rate (99.57±8.11%).
3.Cultivation and propagation of the small scale black fish ( Girella spp.): In this study we want to compare the results of add extracts of different sort and different concentration of algae in the diets to feed the girella (Girella punctata) for six weeks, and collect the growth performance, weight gain, SGR, SOD and Lysozyme data of girella, try to find if different diets would have impact of the growth performance and non-specific immunity of girella. After the experiment, we analyze the data of growth performance, weight gain, SGR, SOD and Lysozyme. In conclusion, there is no significant difference in growth performance, weight gain and SGR of girella for feed different diets; In the Lysozyme analysis, we found the groups which feed extracts of Sarcodia ceylanica (5577.78±1690.64 unit/mL)and sea-tangle (5592.59±2150.20 unit/mL)up to 2% in the diets, have better value and significant difference with other groups. The SOD analysis have same trend as Lysozyme, the experiment groups all have better values than control group.
4.The cultivation and utilization of the ingredients of seaweeds: This study is aimed at the seedling cultivate test and to develop the crude extraction technique of Eucheuma serra, which can improve the additional value and utilization of seaweed. In this study, the seedling cultivate mode of E. serra has been completed. In the crude extraction technique experiment, we divided the samples into hot
extraction group, high temperature and pressure extraction group and homogenization extraction group. In conclusion, the data demonstrates that the total sugar of hot extraction group had significantly higher values than other groups; total phenol of high temperature and pressure extraction group and homogenization extraction group were significantly higher than hot extraction group; The antioxidant capacity, high temperature and pressure extraction group has best values in abilities to scavenge superoxide anion and chelate ferrous ion.