【作者】 杨楚彬；

【导师】 罗琛；

【作者基本信息】 湖南师范大学 ， 动物学， 2003， 硕士

【摘要】 大鲵(Andias davidianus)俗称娃娃鱼，属两栖纲，有尾目，隐鳃鲵科，是世界上最大的珍稀两栖动物和国家二级保护动物。许多学者围绕大鲵的人工养殖和繁殖进行了大量地调查和研究工作，但对输卵管，精巢以及雄性生殖管道的基本组织结构和发育变化尚未见报道。在人工繁殖过程中，发现部分雌性大鲵排卵不顺畅以及产出许多形态不正常的胶膜卵，少数雄性大鲵排出死精子。这些不正常的现象直接影响大鲵的人工受精率。本文开展大鲵的输卵管，精巢以及雄性生殖管道的基本组织结构和发育变化的研究，对了解大鲵卵胶膜形成和精子排出过程，丰富精巢的生物学资料，提高人工繁殖受精率具有重要意义。大鲵的人工繁殖技术取得一定进展，但催产率、受精率和孵化率均较低。我们从亲本饲养模式、判断催产时机、受精稀释液对精子的影响、受精方法和孵化模式等4个方面进行了研究和探讨，以期完善大鲵的人工繁殖技术。结果如下： 一)输卵管的基本组织结构和发育变化 输卵管在性未成熟期，性成熟后的产卵期及退化期的发育形态有明显地区别。他们的组织结构特点如下： 1．不同时期的输卵管壁均由黏膜，肌层和浆膜3层构成，其主要区别在于黏膜的固有层内是否形成分泌腺。 2．产卵期输卵管明显分成伞部，中段和直段，其末端以尖端突入泄殖腔。 3．尖端突的横切面上首次发现有单管腺。其功能有待进一步研究。 二)精巢以及雄性生殖管道的基本组织结构和发育变化 大鲵精巢的表面覆以浆膜，其实质由精细管和精细管之间的疏松结缔组织构成。精巢成熟时，在精巢腹面的纵沟内，精细管相互吻合形成精巢网。从精巢纵沟内伸出一排细长的输出小管。输出小管汇合后进入附睾管。附睾管为一条极度蟠曲的管道，下端与输精管相连。输精管末端以尖端突入泄殖腔。 1．在Ⅳ期精巢内，精细管包含有精原细胞、初级精母细胞、少量精子细胞和支持细胞。同步发育的性细胞群成团分布。支持细胞位于性细胞团的外缘，对生精细胞起支持和营养作用;在V期精巢内，精细管由大量的精子、少量的精子细胞和支持细胞构成。支持细胞体积较大，内含颗粒，能吞噬和消化精子形成过程中脱落下来的残余胞质。精细管的基膜外侧有一圈梭形肌样细胞。精细管之间的间质为疏松结缔组织，富含血管。间质中存在一种间质细胞，成群分布，核圆居中，胞质嗜酸性强。 2.大蜕的雄性生殖管道系统包括4种管道。生殖殖季节时，①精巢网的管腔狭长，腔内充满上皮细胞;②输出小管的豁膜上皮呈指状突起，腔内充满脱落的上皮细胞和分泌物;③附皋管的管腔较圆且小，腔内充满脱落的上皮细胞和分泌物;④输精管的豁膜上皮呈指状突起，肌层明显。在性未成熟时期和退化时期，附皋管消失，其他各管道变小，勃膜上皮不形成突起。 3.在输精管及其尖端突的横切面上发现有单管腺。其功能有待进一步确证。三)关于人工繁殖技术的研究和探讨 三年来对大织人工催产技术进行了试验和探讨，确定了单池饲养模式，首次提出根据大织体重变化来判断催产时机，试验了三种混合液对大鱿精子运动寿命的影响，改进了人工授精以及孵化器孵化技术，成功地孵化出了幼蜕。 1.与大池饲养模式相比，在单池饲养模式下大蜕体重增长显著，死亡率降低，便于管理。 2.资料分析表明，大蜕的群体体重变化情况为确定大织的催产时机提供了客观依据。我们提出根据每个亲本的体重周年变化情况来判断最佳催产期。 3.低浓度的Ho If氏原液和井水(浓度待测)能明显促进精子运动;较高浓度的Ringer氏原液妨碍精子运动。 4.用干湿法授精，添加精子稀释液。受精后把卵带平铺到平底孵化筛内，增开充氧机和微流水，挑出坏卵。更多还原

【Abstract】 As an accidental species, Big Salamander Andias davidians (Amphibia Vrodtle Cryptobrahidae Andias) is the biggest amphibian in the world. It’s protected as II wildlife in China.In this research, the changes of the structure of genitial tube and spermary were studied with the method of histologicial technology at the immature,spawning and catagenetic stages mAndrias davidianus. We also studied the following from four aspects including the model of breeding, the time of enjecting oxytocic hormone, the effect of diluent in fertilization and the model of hatching.The structure of oviductThe morphovar of oviduct was different evidently at the immature, spawing and catagenetic stages. There were the characteristic of histological structure of oviduct.1. In all the three stages the wall of oviduct consisted of three basic layers: the mucous layer, the muscular layer and the serous membrace. Only in spawning season was there secretor on the proper layer of the mucous layer.2. In spawning season, the oviduct differentiated evidently into three parts: the fimbriase of the oviduct, the middle main oviduct and the uterine part. The temination of the oviduct got into the cloacal pore as a apicial segment.3. It was observed at the first time that there were simple tubular glands on the apical egment.The structure of testis and male genital organThe testis was covered with rerous membrance in the surface .and filled with dens connective tissue in deep part. The essence of testis consisted of seminiferous and loose connective tissue betweenseminiferous. When testis matured, seminiferous united to form a testis-net in the ventical with a horizontal. A line of efferent duct extanded from testis-net. Epididymal duct was connected with efferent ducts. It was a long and winding tube.Its end enter deferent duct. The temination ’of the deferent duct got into cloacal chamber a as apical segment.1. In IVtestis, seminiferous epithelium consisted of spermatogenous and sustentacular cell. Spermatogenous that developed synchronizing distributed in mass. Sustentacular cell was at the exterior margin of spermatogenous. In V testis, seminiferous epithelium had spermatozoon, spermatid and sustentacular cell. The sustentacular cell was fat and full of particle. There was a ring of mucle cell beside the basal membrance of testis. Loose connective tissue distributed between seminiferous and was full of blood vessel. There was a interstitial cell in the loose connective tissue. Its cell nucleus was round in the center of cell. Its cytoplasm was sucking much acid dye.2. Genital tubes included four ducts. In the season of genesis, (1) testis-net’s conduit was narrow and it was full of epithelial cell in the conduit.(2)The epithelial lining of efferent duct appeared phalangeal process and it was filled with secretory product in the efferent duct. (3) Epididymal duct was small and round. It was full of secretory product in the epididymal. (4) The epithelial lining of deferent duct appeared phalaneal process. Musular looked obvious. Compared with the stage of mature, allof genital tubes changed much at the stages of immature and catagenetic. Epididymal duct disappeared.The other tubes got smaller. All of the epithelial lining didn’t appear phalangeal process.3. It was observed at the first time that there were simple tubular glands on the deferent duct and its apical segment.The results and improves of the technology of artificial genesis1. Compared with the big-poor breeding model, Andias grew fasterunder the single-poor breeding model. Its death rate fell from 18% to 5%. This model conveniented for management.2. With the analysis of the document, it was clear that the variation of weight was one of the objective standards of determing the time of hasten parturition.In practice the variations of weight of every parent should be surveyed as a scientific basis of hasten parturition.3. The present study indicated that the solution of low concentration promoted the更多还原