拟目乌贼卵子发生与卵巢发育

为了丰富拟目乌贼(Sepia lycidas)生物学资料, 为人工育苗与养殖提供理论依据, 采用解剖学和组织学的方法, 对水泥池养殖条件下拟目乌贼卵子发生和卵巢发育进行了研究。结果表明: 经过6个月水泥池养殖, 平均体重为256.34 g, 最大体重达到457.08 g, 个别发育成熟, 绝大部分未达性成熟。卵子发生不同步, 根据细胞形态、细胞大小、滤泡细胞形态和卵黄形成情况可分为卵原细胞阶段(卵原细胞期)、原生质生长阶段(无滤泡期、单层滤泡期和双层滤泡期)、间质生长阶段(滤泡内折早期、滤泡内折中期和滤泡内折晚期)和营养质生长阶段(卵黄发生早期、卵黄发生晚期和成熟期), 共4个阶段10个时期。卵巢发育根据外观形态、性腺指数变化和切面上各期细胞所占的比例, 可分为形成前期、形成期、小生长期、大生长期、成熟前期和成熟期6个时期。拟目乌贼繁殖周期为一年。  

OOGENESIS AND OVARIAN DEVELOPMENT IN SEPIA LYCIDAS

In order to enrich the content of reproductive biology and provide theoretical guidance for the artificial breeding of Sepia lycidas, the oogenesis and ovarian development of S. lycidas were observed by anatomical and histological methods. Six months after cultivated in the concrete ponds, the average weight was 256.34 g, and the maximum weight was 457.08 g, only single individuals reached to mature, while the vast majority of individuals were immature. The asynchronous oogenesis of S. lycidas could be divided into four periods, and subdivided into ten stages according to the morphology and size of oocyte, the morphology of follicular cell, and the situation of vitellogenesis. The four periods and ten stages were: oogonia period (oogonia), protoplasmic growth period (no follicular cell, single follicular epithelium s, and double follicular epithelium), interstitial growth period (early stage of follicle penetration, middle stage of follicle penetration, and late stage of follicle penetration), and trophoplasmic growth period (early vitellogenesis, late vitellogenesis, and mature oocyte). According to the morphology of ovary, gonad somatic index (GSI), and percentage of oocyte at different stage, the ovarian development could be divided into six stages, i.e.: pre-formation, formation, small growth, large growth, pre-maturation, and maturation. The duration of reproduction cycle of S. lycidas was 1 year.