Comparision On Family Growth And Development Of Early Stage And The Study Of Gonad Development And Reproductive Cycle In Crassostrea Hongkongensis

Crassostrea hongkongensis family were established and be compared growth of early development in this study. We studied various economic traits of C. hongkongensis in order to breed good traits with this species of C. hongkongensis. Family selection is one of effective selection ways for generation of oyster strains. The study was to select six C. hongkongensis with quantitative traits which are quite different as parents and successfully established nine half-sib families. Each family on the fertilization rate, hatching rate, survival and early growth were compared. The results showed that the fertilization rate, hatching rate, survival rate were subject to the maturity degree of the parents, and the growth rate of family CH1, CH4 and CH7 were greater than that of the others. Meanwhile, significant maternal effect was observed on early growth of these families.In addition, histological observation methods was used to study the Guangdong and Guangxi areas C. hongkongensis gonad development and reproductive cycle in this experiment. The results showed that the gonad of C. hongkongensis in Guangdong and Guangxi areas had one reproductive cycle of one year, the reproductive season was from May to September, in which emissions peak from May to July. According to the development law of C. hongkongensis cells and gonadal tissue follicle size, shape and proportion, C. hongkongensis gonad was divided into five periods:the proliferative, growth stage, mature stage, discharge stage, resting stage. There was the phenomenon of hermaphroditism in the Gonad development process of C. hongkongensis.