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STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFI—EYED FLOUNDER, PARALICHTHYS OLIVACEUS （T. et S. ） 总被引：1，自引：0，他引：1
The early effects of chromosomal manipulation of eggs and sperm on the yields of trip-loid and gynogenefic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fen.ilized eggs at 0 - 2℃ for 45 minutes duration 5 minutes after fen.ilization, and the in-duced triploidy rates were 31.2% - 50% and the relative hatching rates were 53.3% - 99%. Gynnge-aetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0 -2℃ for 45 minutes duration 5 minutes after fertihzation. The induced gynogenetic diploid rates and the relative hatching rates were 94 % - 96 % and 48.5 % - 68.5 % respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae ac-cording to Student‘s t-test (α = 0.05). The relationship between the early growth of the triploid experi-mental group larvae and that of gynogenetic diploid experimental group larvae was also studied. 相似文献
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为进一步阐明脊尾白虾(Exopalaemon carinicauda)的繁殖生物学习性, 作者分别以脊尾白虾受精卵和初孵幼体为实验对象, 研究了温度对脊尾白虾胚胎发育及幼体发育的影响。结果表明, 温度对孵化时间及胚胎孵化率影响显著(P<0.05): 在实验温度范围内(19～31℃), 胚胎发育进程随温度升高而加快, 19℃和31℃条件下胚胎孵化时间分别为(536.50±18.33) h 和(218.68±5.51) h; 胚胎孵化率在25℃下最高为64.11%±12.54%, 较高(28～31℃)和较低(19～22℃)温度下的胚胎孵化率显著降低。温度对脊尾白虾幼体发育影响显著(P<0.05): 在16～32℃范围内, 体长增长率随温度的升高而增加, 但幼体发育持续时间随温度的升高而减少, 16℃和32℃条件下幼体变态为仔虾所需时间分别为孵化后(27.60±0.22)d和(7.75±0.07)d, 较低温度范围内(16～28℃)P1变态存活率随温度升高而升高, 28℃的P1变态存活率最高达91.67%±7.64%。但当温度继续升高时, 幼体的变态存活率急剧降低, 36℃时幼体不能变态为仔虾。根据曲线拟合方程推算的最适胚胎发育和幼体发育温度分别为25.33℃和27.60℃。本实验结果可以为脊尾白虾人工育苗的管理提供参考和依据。 相似文献
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人工条件下长蛸(Octopus minor)繁殖习性及胚胎发育研究 总被引：2，自引：0，他引：2
于2009-2010年对山东荣成天鹅湖盛产的长蛸进行了人工繁育研究.采用显微观察和数码拍照等方法,观察其胚胎发育,详细描述各发育期的特征.结果表明,在室温21-25℃、盐度28-31等条件下,长蛸产卵量9-125粒,个体间差异较大.卵长径13-20mm,宽径4-6mm.雌体具护卵行为.胚胎发育期72-89d,分别历经卵裂期、囊胚期、原肠期、器官形成等20个时期.整个发育过程,胚胎发生两次翻转,第一次发生在第Ⅵ—Ⅶ期,约21d;第二次发生在第ⅩⅠⅩ期,约65d,少数个体也存在多次翻转现象.初孵幼体胴背长8.5-11.5mm,全长25-31mm,直接营底栖生活. 相似文献
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Increasing evidence indicates that transforming growth factor β(TGF-P) signaling pathways play many important roles in the early development of mollusks.However,limited information is known concerning their detailed mechanisms.Here,we describe the identification,cloning and characterization of two Smad genes,the key components of TGF-P signaling pathways,from the Pacific oyster Crassostrea gigas.Sequence analysis of the two genes,designated as cgi-smad1/5/8 and cgi-smad4,revealed conserved functional characteristics.The two genes were widely expressed in embryos and larvae,suggesting multiple roles in the early development of C.gigas.The mRNA of the two genes aggregated in the D quadrant and cgi-smad4 was highly expressed on the dorsal side of the gastrula,indicating that TGF-P signaling pathways may be involved in dorsoventral patterning in C.gigas.Furthermore,high expression levels of the two genes in the shell fields of embryos at different stages suggested important roles for TGF-P signaling pathways in particular phases of shell development,including the formation of the initial shell field and the biomineralization of larval shells.The results of this study provide fundamental support for elucidating how TGF-P signaling pathways participate in the early development of bivalve mollusks,and suggest that further work is warranted to this end. 相似文献
99.
作者对鳙鱼胚胎发育早期几个主要阶段发生的内部细微结构变化进行了观察。本文着重观察了卵黄、胚盘、分裂球和囊胚层细胞的形态结构，它们之间的关系以及卵黄多核体的形成。作者在镛鱼卵子受精后所形成的胚盘和以后产生的分裂球中都发现有卵黄颗粒的存在．因而指出，认为卵子在受精后由于卵质分离而形成的胚盘是不含卵黄的看法是不确切的。在鳙鱼胚胎发育的几个早期阶段．作者观察到在胚盘、分裂球和囊胚层细胞与卵黄这种重要物质之间有某种有机联系。本文对卵黄多核体形成的问题连行了讨论。并对前人的某些观点提出了不同的看法。本文着重提到在桑椹期出现的一种深色细胞，在观察了这类细胞的发育和演变之后作者得出结论，认为它们与卵黄多核体的形成有关。 相似文献
100.
