Seasonal variations in the biochemical composition and the reproductive cycle of pen shell Atrina pectinata in Bohai Sea were investigated from May 2013 to April 2014. Histological analysis indicated that the reproduc...Seasonal variations in the biochemical composition and the reproductive cycle of pen shell Atrina pectinata in Bohai Sea were investigated from May 2013 to April 2014. Histological analysis indicated that the reproductive cycle of A. pectinata can be divided into two phases, inactive stage and gametogenesis, which were equally and significantly influenced by seawater temperature and food availability. Gametogenesis began in late autumn(October), and completed in June and July. Spawning took place in August, coinciding with the highest water temperature and the richest phytoplankton. The significantly high glycogen content in adductor muscles sustained throughout the late active and ripeness stages, but plummeted during spawning and inactive stages. The protein content in female gonads exhibited a synchronous increase along with oocyte diameter and lipid content, suggesting that the female gonads could accumulate protein and lipid for vitelline in A. pectinata. Furthermore, the RNA/DNA ratio was found to be a useful index to indicate the level of gonad maturation in both males and females. The findings of the present study provided a foundation for the fishery resource administration and the aquaculture development of this species.展开更多
The pen shell,Atrina pectinata,distributes globally.It is one of the most important edible bivalves in east Asian countries.However,there are multiple difficulties in rearing pen shell larvae and juveniles because of ...The pen shell,Atrina pectinata,distributes globally.It is one of the most important edible bivalves in east Asian countries.However,there are multiple difficulties in rearing pen shell larvae and juveniles because of their high mortality.To understand the mechanism underlining such high mortality at the early embryonic development stage,we obtained approximately 100 million larvae during later breeding season in June,2017,and checked a large amount of mitotic chromosomal plates of the early embryos and post-spawning gonads tissue slices of their parents.The results showed that most diploid A.pectinata embryos have 17 pairs of chromosomes(2n=34)as their parents do.The first pair of particularly large chromosomes are heterotypic in some diploid embryos while they are homomorphic in others.The primary sex-determination chromosome type is XX/XY.A lot of triploid,pentaploid and aneuploid embryos with different numbers of the largest homomorphic or heteromorphic chromosomes were found due to the degeneration of overmatured parent gonads which hold normal karyotype.These larvae will die even though most of them may develop into the trochophore stage with 34 chromosomes.Genetic deficiency of chromosomes will cause a high rate of mortality in early embryos in late breeding season.These findings should enrich the current knowledge of juvenile pen shell aquaculture.展开更多
基金supported by grants from the Scientific and Technical Supporting Program (No. 2011BAD13B01)the National Marine Public Welfare Research Program (No. 201305005)Doctoral Program of Ministry of Education of China (No. 20130132110009)
文摘Seasonal variations in the biochemical composition and the reproductive cycle of pen shell Atrina pectinata in Bohai Sea were investigated from May 2013 to April 2014. Histological analysis indicated that the reproductive cycle of A. pectinata can be divided into two phases, inactive stage and gametogenesis, which were equally and significantly influenced by seawater temperature and food availability. Gametogenesis began in late autumn(October), and completed in June and July. Spawning took place in August, coinciding with the highest water temperature and the richest phytoplankton. The significantly high glycogen content in adductor muscles sustained throughout the late active and ripeness stages, but plummeted during spawning and inactive stages. The protein content in female gonads exhibited a synchronous increase along with oocyte diameter and lipid content, suggesting that the female gonads could accumulate protein and lipid for vitelline in A. pectinata. Furthermore, the RNA/DNA ratio was found to be a useful index to indicate the level of gonad maturation in both males and females. The findings of the present study provided a foundation for the fishery resource administration and the aquaculture development of this species.
基金part by the Central Public-Interest Scientific Institution Basal Research Fund,YSFRI,CAFS,China(No.20603022018004)the National Natural Science Foundation of China(No.31672637)+1 种基金the National Key R&D Program of China(No.2018YFD0900800)the Key Research and Development Plan of Shandong Province,China(No.2016GSF115012).
文摘The pen shell,Atrina pectinata,distributes globally.It is one of the most important edible bivalves in east Asian countries.However,there are multiple difficulties in rearing pen shell larvae and juveniles because of their high mortality.To understand the mechanism underlining such high mortality at the early embryonic development stage,we obtained approximately 100 million larvae during later breeding season in June,2017,and checked a large amount of mitotic chromosomal plates of the early embryos and post-spawning gonads tissue slices of their parents.The results showed that most diploid A.pectinata embryos have 17 pairs of chromosomes(2n=34)as their parents do.The first pair of particularly large chromosomes are heterotypic in some diploid embryos while they are homomorphic in others.The primary sex-determination chromosome type is XX/XY.A lot of triploid,pentaploid and aneuploid embryos with different numbers of the largest homomorphic or heteromorphic chromosomes were found due to the degeneration of overmatured parent gonads which hold normal karyotype.These larvae will die even though most of them may develop into the trochophore stage with 34 chromosomes.Genetic deficiency of chromosomes will cause a high rate of mortality in early embryos in late breeding season.These findings should enrich the current knowledge of juvenile pen shell aquaculture.
