The Key Technical Research On Healthy Larva Breeding Of Haliotis Diversicolor Supertexta

The abalone Haliotis diversicolor supertexta is important species of seashell which is farming in south of china. However in early larval stage of H. diversicolor supertexta died in large quantities these years, it results in a lock of larval, and also it has seriously affected industrialized development of H. diversicolor supertexta. To the problems, several measures have been taken, but no obvious effects have been detected. So this research included gonad maturation, suitable diet and disease prevention, hoping to resolve the problems mentioned above.The research on gonad of parent abalone include hastening gonad to maturation, histology observation of different developing gonad, comparison of hasten result. Photosynthetic bacteria and VE are used as additive. Gracilaria filled with photosynthetic bacteria 150×10^-6 (V/V), VE 5×10^-6.We can find that Photosynthetic bacteria and VE can hasten gonad to maturation more quickly. Look through the observation and biopsy observed in different periods of gonad development, identifying the out characteristics of gonads maturation. We also found that the abalone gonad development obviously does not existing simultaneously mature phenomenon. Gonad develop from the horn department and sustained develop to the medial. In the same cavity of follicular development is not synchronized. There are oogonium, developing eggs and mature eggs. This phenomenon is important on the production. High hasten strength will make immature cells come out. It waste gonad and the survival rate will reduce. We should use appropriately dry, water and other moderate way to let mature sperm and eggs come out. Parent abalones are hastened after raise. Hasten middle mature gonads and mature gonads of female abalone. Contrast fertilization rate, hatching rate and larva condition. The results showed that the fertilization rate, the hatching rate of fully mature gonads is higher.We get small benthic diatoms using meshwork. Expand the plant of small benthic diatoms under the temperature 22-26℃. Management is fertilization, Change water and kills copepods. We provide abalone larva enough and fit food. The results showed that early farming diatom is conducive to the attachment of abalone. Enough food and changing food after abalone eat big alga that can raise larval amount. This shows that enough and fit food can guarantee abalone larval growth, improve larval amount. We suggest several pools used to plant diatoms, supply diatoms when the cultivate larval pools is shortage of diatoms that can avoid death due to food shortages.UV disinfection devices installed on the water inlet pipe. Using UV disinfected seawater to raise larval, at the same time add some iodine to disinfect, Comparing with sand filtered seawater. The results show that the radiation dose at 300 mW·h / L, UV radiation plays a significant role in killing bacteria in the seawater. There are significant differences, compared with the sand filtered water at larval amount. Study shows that the phenomenon of mass death was due to bacteria, viruses and other factors, Control bacteria, viruses should be the focus of disease prevention. UV radiation can kill bacteria and virus in water; it should be the first choice of disease prevention. UV disinfection device are extremely rare using in abalone larval breeding in our country. Its effect is obvious, it should be promoted.There are many factors to impact healthy abalone larval production, Because of the restrictions at time and other conditions, we just gained three conclusion. There are not mass deaths at abalone larval production; it shows that the technical measures have taken are effective.