Comparative Study in Functional Morphology of Antennary Gland of Pacific White Shrimp, Litopenaeus Vannamei, Reared under Various Salinity Condition

The microstructure of antennary gland of Pacific white shrimp was observed and the effect of salinity on this microstructure was studied. The results show that antennary gland consists of coelomosac, labyrinth and nephridial canal. The coelomosac lies in the center of the antennary gland, and takes up most of the gland. The coelomosac wall is composed of podocytes and basement membrance. The projections of the podocytes are connected with the basement membrance. The labyrinth closes the whole gland, and its columnar cells are possessed of microvilli and basal plasmalmmal invaginations. The nephridial canal cells also have microvilli but shorter, its basal plasmalmmal invaginations is deeper and wider. When the shrimp was cultured with lower salinity, the clearance and the volume of coelomosac its antennary gland are smaller, while the length and density of microvilli on the apical side of labyrinth and nephridial canal is longer, the basal plasmalmmal invaginations is wider.