[关键词]
[摘要]
为提高糙海参育苗技术, 研究描述了糙海参从受精卵发育到稚参的形态变化, 在显微镜下测定了受精卵.、 胚胎和幼体的大小, 确定了糙海参胚胎发育的过程。结果表明, 通过利用阴干. 、流水刺激法对成熟亲参进行人工催产, 得到大量的受精卵, 其受精率为90%以上。糙海参胚胎和幼体发育可分为受精卵. 、卵裂期. 、囊胚期. 、旋转囊胚期. 、原肠期. 、初耳状幼体. 、中耳状幼体. 、大耳状幼体.、樽形幼体和稚参等阶段; 在平均水温29 ℃., 平均盐度34条件下, 糙海参受精卵经3 h发育形成囊胚., 4 h进入旋转囊胚期., 5 h进入原肠期. ,19 h完成胚胎发育变态为耳状幼体; 并经过7 d的生长与发育进入樽形幼体; 第15 d天变态为稚参。观察发现, 多精入卵现象则会导致胚胎发育不正常, 最终使胚胎发育停止并死亡。在糙海参幼体发育过程中, 大耳状幼体期幼虫臂的大小及其球状体的形成均可作为判断其幼体发育健康状况的重要指标: 幼虫臂越大,.球状体出现率越高, 其幼虫的变态率和成活率也越高。对比发现, 位于糙海参尾部的突出结构———“尾突”, 为仿刺参(Apostichopus japonicu)和新西兰刺参(Austra-lostichopus mollis)所没有, 这一结构差异同时导致了其骨片位置也不同; 并且, 糙海参胚胎和幼体与其他种类的海参在发育时间上存在一定差异。
[Key word]
[Abstract]
At present, the cultivation of sea cucumber in China is mainly concentrated in the north. The main rearing species is Apostichopus japonicu. However, in the southern part of china China , the high temperature of water is not fit for the cultivation of A. japonicu. As a result, to meet market demand, developing the cultivation of tropical sea cucumber is very necessary. Holothuria scabra is one of common tropical sea cucumbers with high economic value in Hainan. In this thesis, to enhance the seeding technology of H. scabra, the embryonic and larval development of H. scabra was observed and recorded. The heights of fertilized eggs, embryos and larvae were measured under the light microscope, and the time series table of embryonic and larval development was confirmed. The results show that the bloodstocks were spawned artificially by using the method of streaming and drying in the shade jointly. A large number of fertilized eggs were gathered and the fertilized rate was over 90%. The embryonic and larval development of H. scabra can be divided into the following stages: fertilized egg, cleavage, blastula, rotary blastula, gastrula, early auricularia, mid auricularia, late auricularia, doliolaria, pentactula and juvenile. At the average temperature of 29 ℃ and salinity of 34, the fertilized eggs needed 3 hours to develop to the blastula, and 4 hours to the rotary blastula, 5 hours to the gastrula, and 19 hours to auricularia. Then it took about 7 days to develop to the doliolaria and 15 days to develop to juvenile sea cucumber. Through the observation, the conclusion can be drawn that the polyspermy can make the embryo become developmental abnormal. In the end, the development ceased and the creature died. The sizes of larval arms and the appearance of globoid at the big auricularia stage can be used as the important indexes for evaluating the healthy status of the larva of H. scabra. The bigger the larval arms , the higher the appearance rates of globoid were, the higher the metamorphic rates and survival rates of the larva were. Through the comparison with larvae of other kinds of sea cucumbers, the conclusions are obtained that there is a salient structure at the end of larval body of H. scabra, but A. japonicus and Australostichopus mollis have no such organ; while the difference gives rise to the result that the sites of ossicles of different kinds of sea cucumbers are not the same. And, the schedules of the embryonic and larval development are different from H. scabra to other species of sea cucumber. The research could provide dependable data, photos, measures of disease control for the H. scabra larva cultured production to contribute to the exploitation and development of aquaculture of southern sea cucumber. So the market demand could be met and the natural resources could be protected.
[中图分类号]
[基金项目]
海南省重点科技计划项目(ZDXM20100015); 海洋公益性行业科研专项(201205025)