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研究了卵胎生硬盘鱼褐草YouSebastiscus marmoratus精子发生的过程。褐菖You的精子发生经历了初级精原细胞、次级精原细胞、初级精母细胞、次级精母细胞、精子细胞等阶段，最终形成精子。在初级精原细胞和次数精原细胞阶段，细胞核中释放出拟染色体。拟染色体分布于精原细胞和前期I的初级精母细胞的细胞质中。在前期I以后的初级精母细胞、次级精母细胞和精子细胞中，拟染色体已消失。在初级精母细胞阶段，前期I至末期I的细胞形态变化明显。在前期I偶线期，同源染色体开始配对并形成联会复合体；在粗线期，联会复合体完成形成；在双线期，联会复合体开始解体。 相似文献
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Black rockfish（Sebastes schlegeli） is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process of germ cells in this ovoviviparous rockfish in reproductive season（October 2011–November 2012） with histological methods. We found that the gonad of mature fish showed notable seasonal changes in developmental characteristics and morphological structure. The sperm cells matured during a period lasting from October to December, significantly earlier than the oocytes did. A large number of spermatozoa and other cells occurred in testis at different developmental stages. Vitellogenesis in oocytes began in October, and gestation appeared in April next year. Spermatophores were discovered for the first time in Sebastes, which assembled in testis, main sperm duct, oviduct and genital tract, as well as ovarian cavity in October and April. These organs may serve either as production or hiding places for spermatophores and spermatozoa which were stored and transported in form of spermatophores. Testicular degeneration started from the distal part of testis in April, with spermatophores assembled in degenerating testis and waiting for transportation. The copulation probably lasted for a long period, during which the spermatozoa were discharged in batches as spermatophores. These spermatophores were coated with sticky materials secreted from the interstitial areas of testis and the main sperm duct, then transported into ovary. 相似文献
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本研究利用17对微卫星标记对4个许氏平雌本所生家系进行初步鉴别。结果表明,17个位点在家系#1中可以获得的雄亲等位基因数为1—2个,家系#2扩增的雄亲等位基因数为2—5个,另外2个家系中扩增的雄亲等位基因数为2—4个,未出现6个以上等位基因的情况,初步断定,家系#1为一雌一雄交尾的全同胞家系,家系#3和#4是一雌二雄交尾的半同胞家系,而家系#2为一雌三雄交尾的半同胞家系。本文结果可为今后建立以家系为基础的许氏平遗传图谱构建、生产性状的遗传力估算及选择育种体系建立提供一定的理论基础和技术支撑。 相似文献
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贵州发现珍稀古生物化石--鱼龙类卵胎生的新例证 总被引：1，自引：0，他引：1
鱼龙类为适应在水中生活而四肢特化,不能登陆产卵,生殖方式改为卵胎生。通过对一些鱼龙类化石的观察和研究,在我国首次发现了其母体内保存有数具尚未发育完全的小幼体的鱼龙标本,这些化石的发现,为鱼龙类的生殖方式是卵胎生提供了新例证。 相似文献
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卵胎生硬骨鱼褐菖鮋胚胎及仔鱼的发育 总被引：2，自引：0，他引：2
褐菖鮋(Sebastiscus
marmoratus)胚胎和早期仔鱼在卵巢中发育.胚胎发育的营养靠自身卵黄提供.定期从褐菖鱼由雌鱼体内取出正在发育的胚胎或仔鱼,结合体外培育方法观察胚胎及仔鱼的发育特点.从受精卵发育至孵化,胚胎发育期可划分为18期.仔鱼孵出后继续在母体卵巢腔内发育,直至仔鱼开口后离开母体.因此,雌鱼怀胎期长达12d[(15±1)℃].产出的仔鱼大部分器官已建成,卵黄囊即将耗尽,不久开始摄食.实验表明,胚胎和仔鱼在体外培育可以正常发育,在不同的水温条件下发育速度差异较大. 相似文献
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