Improving Maturation Of Oocyte Stripped From Scallop, Chlamys Farreri (Jones Et Preston) By Ammonia Seawater And Serotonin Creatinine Sulfate Complex (5-HT)

Effects of induction were studied to identify the function of ammonia seawater and 5-HT in improving maturation of oocyte stripped from scallop,chlamys farreri (Jones et Preston). The suitable induction parameters were studied. Oocytes induced in vitro and larvae nursery were conducted with observation and analysis on the fertilizing rate, hatchery rate, survival and so on. Effects of induction pH was studied. Also Variation of nucleus during oocytes maturation was observed with fluorescent microscopic determination. This research tried to find a new method of shellfish fertilization artificially and can support shellfish genetic breeding research.Oocytes were stripped and treated by ammonia seawater and 5-HT in vitro, and then fertilized artificially. Results showed that ammonia seawater can induce Germinal Vesicle Breakdown (GVBD) of scallop oocytes remarkably, but the fertilizing rate was low and deformity rate was high.5-HT can not induce GVBD of oocytes, but can induce the maturation of the oocytes already GVBD. Mix treatment was a little better than single treatment, but showed restraint in a way. Oocytes first induced by ammonia seawater then induced by 5-HT was the most suitable treatment, and the fertilizing rate was (40.02±2.73)%.In the research of larvae nursery, eggs induced in vitro developed more slowly than the nomal eggs.The hatchery rate and deformity rate of mix treatment was (16.98±1.66)% and (38.62±5.05)%, while larvaes were little smaller. The hatchery rate of the most suitable treatment was (47.69±1.31)%, lower than the nomal larvaes, but deformity is low. Observation of Paraffin Section showed that the larvae's organs have begun the differentiations.In the research of induction pH, Oocytes'maturation need alkaline conditions. The key factor of improving maturation of oocyte was NH4+, but not pH. In the research of oocytes'observation with fluorescent microscopic determination, the nomal oocytes reached metaphase of the first meiosis at large, but many oocytes induced in vitro were stopped before metaphase, and they need another induction to break the stop, such as 5-HT.