The Morphology Study Of Rainbow Trout Liver And The Effective Caused By "Fu Kang163" On The Structure Of Liver

Rainbow trout (Onchorynchus mykiss) was one important cultivated cold water fish. In order to improve the product quality and stock output, the high fat high protein feed was widely beingused in the cultivating artificial, and it leading to high morbidity of hepatic steatosis in rainbow trout. This study was performed by different chemical stains and transmission electron microscopy to observ the structure features of rainbow trout liver in different development stage. According to the study, the effect of Chinese Herbal Medicine additive "Fu Kang163" on the structure of liver in18month old rainbow trout by feeding practice.The result as follow:1) The liver was coated by tunicle. In8month, the hepatosmatic index was1.25±0.25, The tunicle is about0.72±0.03μm with simple squamous epithelium; there were no collagen fiber and elastic fiber in connective tissue, but with rarely reticular fiber. In20month, the hepatosmatic index was1.60±0.13. The tunicle is about1.14±0.02μm with simple squamous epithelium, there were some collagen fiber and elastic fiber in connective tissue and more reticular fiber embeds in hepatic parenchyma with vessel. In30month, the liver hepatosmatic index was1.83±0.14. The tunicle thickness is added to about1.87±0.08μm, there were more collagen fiber and elastic fiber in connective tissue and plentiful reticular fiber embed in hepatic parenchyma with vessel.2) The parenchymal arrangement was organised in tubules formed by duble hepatocytic plates. The sinusoid was frequently branching and anastomosing with more reticular fiber formed to framework, the reticular fiber in parenchyma was less at8month, the cytoplasm in hepatocyte was less and with numerous vacuolus and glycogen, the sinusoid was numerous and with more reticular fiber at20month old, the cytoplasm in hepatocyte with some vacuolus and more glycogen in30month, ther are more sinusoid in rich, densely reticular fiber was on the sinusoidal line and more bloodcell, and it can be seen fewer collagen fibrils in the space of Disse. The wall of portal vein was thin and with rarely connective tissue. The wall of portal artery was the thickest and rich in collagen fiberin. The bile duct was the more thick, and the content of reticular fiberin its connective tissue was most. The portal tract were classified into four types:(a) bile duct isolated type,(b) biliary-arteriolar tract (BAT) type,(c) biliary-venous tract (BVT) type, and (d) portal tract type, biliary-arteriolar-venous tract (BAVT) type. The type of portal area was mainly in bile duct isolated type in8month, and mainly in biliary-arteriolar tract (BAT) type in20month, otherwise the biliary-arteriolar tract (BAT) type and biliary-arteriolar-venous tract (BAVT) type were mainly in30month.3) The hepatocytic contained considerable amount of rough endoplasmic reticulum, glycogen particles, mitochondria, and so on, the nucleus was spherical, the plasma memberane was formed more microvilli into the space of Disse, there is rarely collagen fiber. There were macrophage and erythrocyte in sinusoid. The sinusoidal endothelial cell was flated, included small mitochondria, some rough endoplasmic reticulum (RER). The cytoplasm was not continuous and with numerous fenestrae. There were no basal memberane on the beneath of these cells and no junction complex between them, and neighbouring endothelial cells overlapped and interdigitated, nuclei were generally elongated, bulging into the lumen. The hepatic stellate cell (HSC) was located in the space of Disse, immediately underneath the endothelial lining, had elongate, angular nuclei, rich in heterochromatin. The cytoplasm was contained mitochondria and rough endoplasmic reticulum, cytoplasmic processes of the PSC were frequently observed was linked to adjacent cells, the heterochromatin of hepatocyte was rarely, the lysosome in hepatocyte, the pinocytotic vesicle and phagocytic vacuolus were less all in8month, there were numbers lysosome, pinocytotic vesicle and phagocytic vacuolus in20month, there were heterochromatin and the lysosome in hepatocyte, the pinocytotic vesicle and phagocytic vacuolus were more in30month.4) The elements of portal area of the7%dose group were more than the other group, showed significantly difference after feeding with the "Fu Kang163"60days The number of melanmacrophage of the5%dose group were more than the other group, demonstrated significantly difference. The vesiculation degree of the dose of5%and7%group were obviously lower than the control and3%groups. So the study demonstrated that when the feed with the proper supplement of "Fu Kang163", it can be promoted the fatty metabolism, promoted the rainbow trout development. So it is advisable that5%"Fu Kang163" additive in feed of rainbow trout.Conculsion:This study is showed that there is close relationship between the function and regulation of rainbow trout and the different physiological stages. In juvenile stage of rainbow trout, the feed need relatively lower protein and fat, when mature period, about20month, the structure of liver was development well, the metabolism was more strengthen, the feed need relatively moer protein and fat, which can promoted the rainbow trout development.