Study On The Reproductive Biology Of Artificial Feeding Andrias Davidiamus

We began the research on artificial feeding of Chinese giant salamanders on macroscopic and microscopic aspects in March 2000. We studied principally the relationships of artificial feeding and artificial reproduction,growth,prey,feeding pattern,the gonads of maturity,induction of ovulation ,artificial reproduction.During the experiments of prey,the analyses of feeding patterns,the relationships between growing speed and age,and between growing speed and feed,we discovered that Chinese giant salamanders like the crabs best,then frogs and loaches and then small fishes . Giant Salamanders were not very interested in entrails and different kinds of insects which were dead. Under the same density,Giant Salamanders with different weights,ages and feeds grew at different speeds. In particular,Giant Salamanders which were bred with artificial mixed feed grew most quickly,then with crabs and frogs,with different kinds of small fishes grew most slowly .The reason of this phenomenon was that the nutrition of mixed feed was the most adequate.During the experiments of sex ratio and carrying ovum quantity,the sex ratio of giant salamanders was about 1:1 .The absolute carrying germ cell's quantity of Giant salamanders increased with weight increasing. On the contrary,the relative carrying ovum quantity of Giant salamanders reduced with weight increasing. The relative carrying ovum quantity of Giant salamanders was the highest just after gonads mature. Body weights wereabout500-1000g.On the other hand,during the experiments of artificial reproduction,we discovered that the maturity of gonads,qualities of sperm and ovum of giant salamanders were tightly connected with foods,different types quality of hormones and effective time.On the microscopic aspect,the microstructure and ultrastructure of oocytes,testes,spermatic ducts and oviducts walls of Chinese winter giant salamander were observed with light and electron microscopes. Structures of big and small oocytes and testis cells were investigated in detail . Mitochondrion closed to the nucleus were composed of primitive mitochondrion. They did not form clear cristate,some of them weremultiplied in these areas,the mitochondrion distributed in the ooplasm were mature with clear cristate. In addition,we particularly analyzed the structures of oviducts and testes of Chinese Andrias Davidianus ,mucous cells with different shapes,phrases of oocytes and sperm cells ,the changing reason of Mitochondrion in oocytes ,the differences between the walls of oviducts of Chinese giant salamanders and Rana Temorria Chensinesis,and between testis,spermatic ducts of giant salamanders and other amphibious were discussed in this paper.