高腰海胆胚胎及幼体发育过程

Embryonic and larval development of sea urchin Mespilia globulus

为开发高腰海胆Mespilia globulus人工繁育技术,对高腰海胆进行了人工催产、授精、孵化和幼体培育,在显微镜下观察了高腰海胆从受精卵到稚胆的发育过程,并测量了受精卵、各期胚胎和幼体的大小。结果表明:利用注射KCl溶液法催产,可以顺利促使高腰海胆排放精卵,排出的精卵受精率为92.3%±1.4%;高腰海胆胚胎和幼体发育过程包括受精卵、卵裂期、囊胚期、旋转囊胚期、原肠期、棱柱幼体、二腕幼体、四腕幼体、六腕幼体、八腕幼体和稚胆等阶段;在水温为25~26℃条件下,受精卵在50 min后开始卵裂,10 h后进入旋转囊胚期,15 h后进入原肠期,23 h后进入棱柱幼体期,1 d 14 h进入二腕幼体阶段,2 d 10 h进入四腕幼体阶段,7 d 13 h后进入六腕幼体阶段,9 d 18 h后进入八腕幼体阶段,11 d后变态为稚胆。研究表明,高腰海胆各期浮游幼体尺寸与其他海胆种类相近,但浮游期相对较短,人工育苗难度相对较低。

To develop artificial breeding techiques of sea urchin, artificial spawning, artificial fertilization, hatching and larvae cultivation were conducted in sea urchin Mespilia globulus. The embryonic and larval development of the sea urchin was observed, and the size variations in fertilized eggs, embryos and larvae were measured under a microscope. The results showed that the spawning of brood stock was induced by injecting KCl solution, with artificial fertilization rate of(92.3±1.4)%. The embryonic and larval development of Mespilia globulus can be divided into the following stages: fertilization egg, cleavage, blastula, rotary blastula, gastrula, prism larvae, two-armed larvae, four-armed larvae, six-armed larvae, eight-armed larvae and juvenile. At temperature of 25-26 ℃, the fertilized eggs started cleavage in 50 min, and went into rotating blastula stage in 10 h, and went into gastrula in 15 h, and went into prism larvae in 23 h, and went into two-armed larvae in 1 d 14 h, and went into four-armed larvae in 2 d 10 h, and went into six-armed larvae in 7 d 13 h. It took a total of 9 d 18 h for fertilization eggs to develop into eight-armed larvae stage, and 11 d to develop into juvenile stage. The sizes of different stage larvae were comparable with those of other sea urchin species, however, the pelagic period was shorter in Mespilia globulus than that in others and this will be benificiac to artificial breeding.