The histology and ultrastructure of the hepatopancreas of the Mozambique tilapia, Oreochromis mos­sambicus

Abstract

The histology and ultrastructure of the hepatopancreas of the Mozambique tilapia O. mossambicus are described. The liver is surrounded by a thin connective tissue capsule. The hepatocyte arrangement shows as lobules, with the hepatocyte cords that radiate and anastomose from a central vein. Borders of individual liver lobules do not show clearly, as do the few triads found in the liver of O. mossambicus. Each hepatocyte contains a single round nucleus with a prominent nucleolus. The rough endoplasmic reticulum appears in two or more rows around the nuclei and in close proximity to the plastnalemma of the hepatocytes. The remaining cytoplasmic organelles are scattered throughout the hepatocyte cytoplasm. The exocrine pancreas cells are centred around the portal veins. The nuclei of these cells are spherical and hasally situated in the cubiform to cylindriform cells. Well developed rough endoplasmic reticula - vesicular, tubular and circular in appearance - as well as secretory granules, apically situated in the cells, are present.