Primary Studies On The Ovary Development And Oogenesis Of Coreius Guichenoti

From Oct. 2001 to Oct. 2002, 165 Core/us guichenoti was collected in Ghangjiang River and the Jinsha River. The structure of oocyte of Core/us guichenoti was observed by means of ordinary anatomy, light microscope, transmission electron microscope. The results are as follows:Core/us guichenoti has a pair of ovaries, which are located at the two sides of swim bladder and alimentary canal, and attach to the abdominal part of kidney. The two ovaries join together at the end, which lead to ureter by a very short oviduct. The ovary development is divided into stages I V according to the external feature, color, size, weight, SGD(sexual gland index), blood vessel's distribution, histological and cytobiological characters of oocyte. The present paper reports stages I -IV. As for the stage I , the ovary is relatively slim in the shape of thread. During the stage II, the volume of the ovary gets bigger in the shape of "V". There is no blood vessel and it can be separated from kidney by means of Bouin's liquid. In the stage III, we can see red because of the distribution of blood vessel, and we also can see leaves shape by means of fixation. Since oocyte does not fill the ovary during the early period of this stage, we can see the transparent ovary membrane. With the development of oocyte, the ovary is filled by oocyte. As for the stage IV, we can clearly see oocyte. Blood vessel distributes on the ovary, which gets in the shape of bag. During the early period of this stage, the ovary is caesious and attaches to each other while their color turns gold by separated ways. The oogenesis also can be divided into phrases I - V according to the following characters: the size of oocyte, the number and volum of nucleolus, the change of karyoplasm and karyothec, the appearance and change of yolk nucleolus in cytoplasm, the distribution of granulose cell, vacuole, and yolk granule as well as the histological traits of the components and change of follicle cell. This paper reports phrases I -IV. As for the phrase I : oogania are close to each other and distribute in groups. Most of the cells are round with one nucleolus which is prone to absorbing alkali and has the big ratio of nucleus to cytoplasm. In the phrase II, the distinctive traits are as follows: oocyte goes into the small growth stage; the number and volume of oocyte get bigger and bigger; the ovarian wall forms spawning plates which comes tofill the ovary cavity. In the course of early period of this stage, the karyon forms into beads-like shape, and its plasma is the silk shape. The number of nucleolus gets bigger; follicular cells begin to scatter around the oocytes, and oogonia still take a remarkable proportion. In the middle period of the phrase II, loop of growth helps to form the different chromatin area. With the development of oocytes, loop of growth also developes till disappears. When yolk vacuole appears on the verge of cytoplasma, the development of oocytes goes into the phrase III. As for the phrase III, the vacuole extends to the area of nucleolus till it fill cytoplasm; the yolk granules extend with the movement of vacuole. The yolk granules have different morphological structure in different areas; the big nucleolus are different from those little ones, and there is also excluding phenomenon of karyoplasm. The ability of absorbing acid of cytoplasm becomes stronger. Cytoplasm only appears in the area of cortical layer. The vacuole and yolk granules are filled in the cytoplasm; in the middle period of this phrase, zone radiata appears; there are many capillaries appear among the oocytes; follicular cells increase and form one layer flat follicle cells. As for the phrase IV, vacuole begins to degenerate and its number decreases, while yolk granules begin to fill the cytoplasm. Yolk granule has the tendency to conjugate together; some nucleolus membrane disappears and diffuses into cytoplasm; there are many nucleolus in small volume, zone radiata gets thicker and its channel become very apparent; follicular layer differentiate into two layers. The...