西藏黑斑原鮡胚胎发育观察  

Embryonic development of Glyptosternum maculatum in Tibet

作　　者：潘瑛子 李宝海 格桑加措 刘海平 周建设 PAN Yingzi;LI Baohai;KELSANG Gyatso;LIU haiping;ZHOU Jianshe(Tibet Academy of Agricultural and Animal Husbandry Sciences,Institute of Fishery Sciences,Lhasa 850032,China;Maizhokunggar County Forestry Bureau,Lhasa 850200,China)

机构地区：[1]西藏自治区农牧科学院水产科学研究所,西藏拉萨850032 [2]西藏自治区拉萨市墨竹工卡县林业局,西藏拉萨850200

出　　处：《中国水产科学》2018年第6期1205-1215,共11页Journal of Fishery Sciences of China

基　　金：农业部公益性行业(农业)科研专项(201403012);西藏自治区财政专项(藏财指(专)字[2014]69号)

摘　　要：黑斑原鮡(Glyptosternum maculatum)是中国唯一的原鮡属鱼类,仅分布在中国境内的西藏雅鲁藏布江水系。由于过度捕捞、水利工程影响、外来鱼类入侵等原因,其野生种群数量持续下降,分布范围逐年缩小,目前处于极危状态。本研究中黑斑原鮡亲鱼捕自西藏日喀则市谢通门县、拉孜县、昂仁县、萨嘎县4个地区的雅鲁藏布江江段,采样地海拔分布范围介于3900～4500 m。2015年5月中旬至6月中旬,人工催产雌鱼79尾,自然排卵7尾,解剖雄鱼15尾进行授精,得到了黑斑原鮡受精卵约42208粒。受精卵为圆形的沉性卵,略显淡黄色,黏性较强。将受精卵平铺放在特制筛网上,置于微流水的平列槽内进行孵化。观察从受精卵至仔鱼孵化出膜的胚胎发育过程,统计有效积温。结果显示:黑斑原鮡胚胎发育时序符合硬骨鱼类胚胎发育的一般规律,分为8个阶段,即受精卵、胚盘形成、卵裂、囊胚、原肠、神经胚、早期器官形成及孵出阶段。胚孔封闭前就形成了肌节和眼囊,进入早期器官形成阶段后依次出现了耳囊、心脏原基、消化道、耳石、眼睛体、胸鳍原基等,心脏搏动后红细胞也有出现。整个胚胎发育期间的平均温度约为13.8℃,有效积温为2963.2～3132.4 h.℃,孵化率约为70%。本研究还发现黑斑原鮡胚胎具有双层卵膜的特殊结构,该结构在成熟卵吸水膨胀后形成,进入神经胚期完全消失,分析推测这种结构可能与对环境的适应有关,外层卵膜在卵的传播和孵化过程中可以起到黏附固定和缓冲保护的作用。本研究旨在深入了解黑斑原鮡胚胎发育的特点及规律,为黑斑原鮡资源恢复及科学保护提供理论参考。Glyptosternum maculatum is the only species of Glyptosternum in China and is uniquely endemic to the Yarlung Tsangpo River system. With the rapid dwindling of its populations and gradually shrinking distributions due to overfishing and the impact of water conservancy projects and foreign fish invasion in recent years, it is considered a critically endangered （CR） species by the Red List of Chinese vertebrates （2015）. It is the only one of the 77 known Chinese sisorid species to be ranked on this list. In this study, the broodstock were captured in the four Yarlung Zangbo River sections of Shigatse, Tibet, including Xaitongmoin, Lhatse, Ngamring, and Saga. The altitude distribution range of the four sampling sites is approximately 3900–4500 m. From mid-May 2015 to mid-June 2015, 79 females were artificially induced to spawn, another 7 females naturally produced eggs and about 57440 eggs were spawned. At the same time, 15 males were dissected and their testes were broken for use in artificial insemination. Approximately 42208 fertilized eggs of G. maculatum were obtained. The fertilized round, demersal eggs were slightly yellowish with strong viscosity. The fertilized eggs were laid flat on a special sieve net and hatched in a small trough of a running water. In Lahsa, Tibet, the entire embryonic development process from fertilized egg to hatching was observed and the effective accumulated temperature of the embryonic devel-opment was calculated. In the fertilized egg and cleavage stage, the same batch of fertilized eggs were sampled, observed, photographed and recorded every 30 min. After the cleavage stage, samples were taken every 1 h. At each time point, 10 fertilized eggs were taken and the stages of embryonic development and the period for entry into each were examined by microscopy. More than 50% of the embryos appeared to have corresponding charac-teristics. It was found that the timing sequence for embryonic development of G. maculatum was consistent with the general rule of teleosts, divided in

关 键 词：黑斑原 胚胎发育 形态特征 时序性 双层卵膜 雅鲁藏布江 西藏 

分 类 号：S917[农业科学—水产科学]