Black Snake Follicle Development Microstructure And Ultrastructure

Zaocys dhumnades(Serpentiformes:Colubridae) are large non-toxic snakes particular in china, which are located in south region of China's Huaihe River and Qinling Mountains,mainly feeding on batrachia,playing an important role in maintenance of balance between agriculture,forestry, ecological system.In this paper,the morphologic characters and varieties of oocyte,follicular cells, zona pellucida,atretic follicles,and corpora lutea in sexual mature Zaocys dhumnades during follicular development were observed by light microscopy and transmission electron microscopy techniques.The significances of the work lie in,not only for understanding the law of development in Zaocys dhumnades,enriching contents of vertebrate reproductive biology,but also for artificial feeding and reproduction of Zaocys dhumnades,the effective conservation of wildlife resources, rational development and use.The main results and conclusions were as follows:1.The large follicles/ovums were only in the ovary of June,ovums in fallopian tube were in June and July.Based on the results and reported data,Our results suguset that ovulation period of Zaocys dhumnades in Qingling region is in June.2.Only one germinal bed was seen in each ovary,but more eggs spawned.The results showed that the clutch size of Zaocys dhumnades was no directly related to the number of germinal bed in each ovary,which was different from the Lizard.The more spawed eggs might be controlled by the total number of follicles per germinal bed and the number of vitellogenic follicles,which achieved the goal of races conservation.3.Acording to the time,the location,the shape,the structure and the characteristics of the latter development,the follicular wall may be double origin:granulosa cells were from the surface epithelium of germinal bed,thecal cells were from somatic cells in ovarian stroma.4.The heterogeneous granulose in Zaocys dhumnades consisted of three types of cells:small cells,pyriform cells and intermediate cells.At first,granulose layer were only composed of small cells,the appearance of pyriform cells followed,intermediate cells were appeared at latest.The development of granulosa cells in Zaocys dhumnades was similar to Gekko swinhonis,which was different from other squamate reptiles.The results not only showed that Zaocys dhumnades was related to G.swinhonis,but also suggested that the development of heterogeneous granulose in squamate reptiles was multifarious.Moreover,the appearance and disappearance of heterogeneous granulose in Zaocys dhumnades were similar to that in other squamate reptiles and rhynchocephaliformes,which were not seen in crocodiliformes and chelonia,offering morphological basis for Multi-source theory of the origin in reptiles.5.Analysing the change of the mitochondria,Golgi body,the vacuole,particles in oocyte,lipids in follicular cells,lipids and coated vesicles structure,The vitelline substance of Zaocys dhumnades can be divided into endogenous and exogenous.6.According to the distribution,morphological characteristics of yolk particles and yolk platele, Our results showed that the yolk material deposited of Zaocys dhumnades firstly were arrounding the nucleus,then gradually expanded to the verge of the oocytes.Yolk platele formation was:â… â†'â…¡â†'â…¢.More over,Analysing the mutual integration of the structure in previtellogenic stage and vitellogenic stage,yolk platelets of Zaocys dhumnades were formed by lipids,the yolk of a deposition mitochondria,glycogen granules and vacuole mutual gradually fused together.Our results showed that the formation of yolk platelets in Zaocys dhumnades resulted from the harmonious activity of the ooplasm and the organelle,vitellogenesis are diverse rather than unitary.7.The zona pellucida of Zaocys dhumnades was originally formed discontiguous patches,then gradually formed a integrated layer.The pattern was similar to Tarentola mauritanica.Whether the phenomenon is a common feature of squamate reptiles,reptiles,even amniotic category,we need to be further accumulation of information to conclusion.8.The corpora lutea of Zaocys dhumnades was separated by connective tissue fibers,cell surrounded acinus was sigle layer.Our results showed that the arrangement of lutea cells in Zaocys dhumnades was different from mammalian and human.