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通过实验室研究,对石磺(Onchidiumsp.)胚胎发育过程进行了详细观察,比较了不同水温下石磺胚胎发育的速度,探讨了膜内面盘幼虫孵化出膜的主要条件。结果表明:石磺的胚胎发育过程类似于肺螺亚纲其他贝类,行体内受精,刚产出的卵为受精卵,细胞未进行分裂,卵裂从卵产出体外开始,分别经过卵裂期,囊胚期,原肠期,膜内担轮幼虫期,膜内面盘幼虫期,经过孵化期孵化出膜为自由生活的面盘幼虫期。对各阶段幼体的大小、形状、内部器官等特征以及发育变态过程进行了详细的显微观察和描述。26℃,28℃,30℃3个水温组中,从受精卵到膜内面盘幼虫孵化出膜分别需要300h,290h,288h;发现影响幼虫孵化出膜的主要因素是水温和海水的刺激作用;繁殖盛期卵群工厂化水泥池自然水温孵化时间为10~14d。并报道了水温低于23℃时石磺胚胎停止发育现象。
Through laboratory research, we observed the embryonic development of Onchidium sp. In detail and compared the developmental speed of the stone embryos under different water temperatures. The main conditions for larvae to hatch out of the membrane were discussed. The results showed that the embryonic development of stomatal was similar to that of other shellfish in the family Smuliaceae. The eggs were fertilized in vitro and fertilized eggs were not produced. The cleavage did not start from the egg in vitro and passed through the cleavage Stage, blastocyst stage, gastrula stage, larval stage of larvae in membrane, larval stage of lacunar disc, hatching out of larval stage for free-living larvae after incubation. The larval size, shape, internal organs and other characteristics as well as the development and metamorphosis process of the larvae were studied microscopically and described in detail. In the three water temperature groups of 26 ℃, 28 ℃ and 30 ℃, the larvae hatching from the fertilized eggs to the inner surface of the membrane lasted for 300h, 290h and 288h respectively. The main factors influencing larval hatching were the water temperature and seawater stimulation. Breeding period egg plant cement pool natural water incubation time is 10 ~ 14d. It was also reported that when the water temperature is lower than 23 ℃, the development of stone embryos stopped.