Studies On Basic Histological Structure Of Genital Tube And Testis And Technology Of Artificial Genesis In Big Salamander, Andrias Davidians

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...