Studies On Structure Of Reproductive System And Oogenesis In Sepia Esculenta Hoyle

Based on golden cuttlefish(Sepia esculenta Hoyle)as the research object,a detailed description of the histological characteristics of the reproductive system and oogenesis,the specific contents are as follows: the reproductive system of golden cuttlefish(S.esculenta Hoyle)was observed using anatomical,histological methods and electron microscopy,and made a detail description.At the same time,the ovarian cycle development and oogenesis of the cuttlefish were observed.The morphological characteristics,development rules of the ovary,the structure characteristics and the dynamic changes of the ovaries in each phase of the S.esculenta were described by the methods of anatomy and histology in detail,and the stages of ovarian development and oogenesis were staging.1.Structure of female reproductive system of S.esculenta Hoyle: The female reproductive system consists of ovary,oviduct and oviducal gland,affiliated gland(including nidamenta l gland and accessory nidamental gland).According to the light microscope,ovary consisted of ovarian wall,different periods of oocytes and its parenchyma.The nidamental gland was found to consist of a nidamental wall and many lamellae;Lamellae containing two types of cell: secretory cell and support cell.The ultrastructure of the secretory cells was examined using Transmission Electron Microscope(TEM).There were numerous mitochondria,golgi apparatus and a lot of granules in the cells.Support cells had less of organelle.The accessory nidamental gland was more complex than the nidamental gland,the accessory nidamental gland was found to consist of accessory nidamental wall,many tubules and connective tissue.Tubules is base structure of the accessory nidamental gland,the lumen surface has microvilli layer.The lumen of tubules had a large of symbiotic bacteria;the tubules consists of a single layer of epithelial cells.Tubular epithelial cells near the lumen side have a lot of microvilli and cilia,cytoplasmic dense and uniform,cytoplasm contains a lot of sizes vesicles,have abundant rough endoplasmic reticulum,mitochondria,and golgi apparatus.Acorrding to ultrastructure of the nidamental gland and the accessory nidamental gland,we suppose that the nidamental gland and the accessory nidamental gland may play a secretory role in the reproductive cycle.2.The oogenesis and ovarian development of S.esculenta Hoyle: The main features of S.esculenta Hoyle oogenesis showed that the follicular cells always existed and were associated with their structural changes before oocyte maturation.The disintegration of follicular cells and the occurrence of yolk substances occurred synchronously.The egg yolk substances accumulated from nothing to a large amount of accumulation until the whole oocyte was full,and the follicle cells were completely disintegrated.The nucleus was gradually shifted to the final disappearance with follicular cells.The study also found that the eggs in the S.esculenta Hoyle ovary were not synchronization and morphological differences were significantly.The immature oocytes were adhered to the ovarian matrix and circulated around the matrix of the ovary in turn,the closer to the center,the lower degree of the oocyte development.After maturation,the oocytes were free in the ovarian cavity and were discharged through the oviduct.The asynchronous oogenesis of S.esculenta Hoylecould be divided into five stages with nine phases,proliferative stage(oogonia phase),small growth stage(free follicular cell phase,single follicular cell phase,double follicular cell phase),large growth stage(follicle penetration phase,pre-vitellogenic phase and late-vitellogenic phase),maturation stage and resorbing stage,according to the morphology of oocytes and follicular cells and vitellogenesis.Based on oogenesis,ovarian development cycle could be divided into six(I~VI)stages,according to the appearance of the ovary and the proportion of the oocytes of the cutting surface at each phase.3.Structure of male reproductive system of S.esculenta Hoyle: S.esculenta Hoyle is reproductive system more complex than bony fishes,the results showed that the male reproductive system consists of spermary,vas deferens,vesicular seminalis,spermatophore sac,prostate gland,vesicula seminalis and penis.According to the light microscope,spermary consists of numerous seminiferous lobules.There are germ cells which are different times in the seminiferous lobules.And there are cilia in the spermatophore organ,in favor of sperm transpotion.