A scanning electron microscopic observation of the gill of yellowfin porgy Sparus latus and Nile tilapia Oreochromis nilotica

Regular and irregular circular microridges, indentations, micropits and crevices were observed in the gill of yellowfin porgy Sparus latus and Nile tilapia Oreochromis niloticus by scanning electron microscopic examination. Some surface of gill filaments of S.latus was rude and the other area was smooth. Morphology and distribution of gill epithelial cells in S.latus and O.niloticus showed some small difference. The limit of pavement epithelium cell in S.latus was well defined by the hexagonal or rhomic quadrangular shapes, but the surface of pavement cells in O.niloticus was characterized by dense finger-print shaped microridges with fine lateral protuberances on both sides. Clear definition of cell boundaries were formed by the rude surface with indentations and micropits. S.latus had numerous chloride cells and mucous cells in the gill, while no chloride cells and few mucous cells were found in the gill of O.niloticus. The secondary gill lamellaes in S.latus was thicker than in O.niloticus.