Histological Study On Follicular Of Anser Cygnoides Linnaeus

Seven female Anser cygnoides Linnaeus (3-4years) that were in oestrum and anoestrumwere used to explore the changes of histological structure during follicular development withlight and electron microscopes. The results were as follows:1. Primordial follicle consisted of an oocyte and a single layer of flat follicle cells, and theaverage diameter of primordial follicle were 37.09μm. One to layers of follicle cellssurrounded the primary follicle around which follicular theca gradually came into being. Theaverage diameter of primary follicle were 113.38μm. Oocyte of secondary follicle wassurrounded by over four layers of follicle cells. The average diameter of secondary folliclewere 155.41μm. The cytoplasm of oocyte of the mature follicular were extruded to the cellmembrane, the structure of which is typical zona radiate.The average diameter of teriaryfollicle were 4.53cm. The follicles there was no follicular antrum and follicula succus.Therewere many capillary in the follicle plasma membrane.The ektexine of follicle were degeneratesoon after ovulation and no corpus luteum come into being.2. At the beginning of primordial follicle's atresia, the oocyte presented regressive changesand shrinking, the nucleus of follicular cells became pycnotic. During primary and secondaryfollicle's atresia, the oocyte began to deform and shrink, its nucleus became pycnotic, zonaradiated deformed, the basal lamina disappeared, the follicle's shape became irregular, and itsnucleus got to be very compact. The teriary follicle's atresia included early, advanced and latethese three stages.3. The shape of primordial foUicile cells in which there was few organelles was spindly orlong and flat. Much heterochromatin along the nucleus could be seen clearly and the nucleushad a large proportion in these follicle cells. In the cubical or unilaminar follicular cells, thenucleus became round or elliptic and located on the bottom, the number of organelles increased,and the structure of organelles became clearer. In primary and secondary follicle cells,mitochondria was round or elliptic, which was often surrounded by rough endoplasmicreticulum, the free ribosome could be seen a lot, and the projections of follicle extendedthrough zona pellucida. In the cytoplasm of the teriary follicle, there were many Golgi complex,endoplasmic reticulum and ribosome. Microfilaments widely lied in the cytoplasm ofgranulose cells.4. During different developing stages of the follicles the oocytes' ultrastructure had manychanges. At primordial follicle stage, the oocyte was round and its plasma membrane smoothlysticked to the follicle cell's, most organelles located near the nucleus, Golgi complex was nottypical, and most mitochondria with few Cristae were round. At primary and secondary follicle stage, follicles locally formed zona radiate when they consisted of three to four layers offollicle cells or the diameter of follicles over 7 mm.when they were preponderate over 7 mmpresent in the zona radiate were thin.Organelles were well distributed in the cytoplasm, and thenumber of mitochondria, cortical granules and smooth endoplasmic rericulum had all increased.At teriary follicle, zona radiate became thick, the number of rough endoplasmic rericulumdecreased obviously, and all kinds of organelles and Golgi complex increased in the cortex, anda lot of cortical granules began to laid beneath the plasma membrane of oocyte. In the cortexmost organelles distributed and there were many Golgi complex.