Histogenesis Of The Mongolia Sheep Embryonic Liver And Spleen

Using the normal technique of histology and electronic-microscope to study the development of sliver and spleen in period of embryo of sheep, when the length of embryo was in 4mm~10mm,the hepatic diverticulum occurred. In the length of 37mm.the vein cave was occurring; in 65 mm, the central vein started emerging; in 164mm, the liver lobule was clearly. In 15mm, there are plenty of blood vessels. The porta area was occurring in the 85mm and the distinction between the artery and vein was not obvious in the early embryo. The typical porta area appears in 250~300mm.Befour the liver lobule forming, the shape of hepatocytes were polygon and the liver cells assembled. As the liver increasing and the liver lobule forming , 1-2 layers of cells arrange in the liver cell cords. After 400mm , the cytoplasm of hepatocytes were loosely, they seem as puffy and soft. There were light and dark cells in electron microscope. In 15mm, the blood-forming focus were appearing, the blood-forming function reached height level in 164mm~250mm and it existed already in 510mm.Tne spleen of sheep come from the mesenchyme of gastral capsule in the period of embryo .There were a little of red cells. The white pulp and red pulp appeared in 115mm, the marginal zone appeared in 480mm, the ellipsoid appeared in 400mm in the red pulp. The spleen nodule was occurring in 347mm, the blood-forming tissue was occurring in 85mm, the lymphatic cell appeared in 115mm, the blood-forming function reached height level in 200mm and it existed already in 480mm. The member of huge nuclear cells changed as the function of blood-forming.