金乌贼胚胎发育的研究

Observations on the embryonic development of Sepia esculenta Hoyle

对人工孵化条件下金乌贼的胚胎发育进行了观察。刚产出的卵子,均重0.99g/粒(n=100),长轴为11～24mm,短轴为8～15mm,卵黄如鸡蛋状,梨形,长径5～6mm,短径3～4mm,外包三级卵膜。三级卵膜在胚胎发育过程中经历一个柔软-定形-缩小-膨大的变化过程。受精卵在20～25℃水温下孵化,经过26d幼体陆续脱膜孵出。根据胚胎发育的外部形态及典型特征将金乌贼胚胎发育过程划分为细胞分裂期、囊胚期、原肠期、器官发育期、出膜期5个典型时期。在胚胎发育过程中,眼的形态变化比较大,且经历一个无色、红色再到黑色的变化过程。

The embryonic development of golden cuttlefish under artificial hatching conditions was observed. The average weight of newly spawned eggs is 0.99 g/particle （n=100）,and the major axis is 11～24 mm,the minor axis is 8～15 mm. Egg yolk is egg-shaped,pear-shaped,with long diameter of 5～6 mm and short diameter of 3～4 mm,and is wrapped by three-egg-membrane outside. Three-egg-membrane in the embryonic development processed a soft-figuration-narrow-enlargement change. The fertilized eggs hatched at water temperature of 20～25℃,and the larvae hatched out about after 26d hatching. In terms of the exterior appearance and the typical characteristics,process of embryonic development includes 5 stages：cleavage stage,blastula stage,gastrulae stage,organ development stage and hatching stage. In the embryonic development process,the morphological changes of the eye were relatively large,and it turned from colorless,red into black.