Localization of the vitellin and its possible precursors in various organs of parapenaeus longirostris (crustacea, decapoda, penaeidae)

Histological studies and immunofluorescence revealed two phases of cytoplasmic development during oogenesis of Parapenaeus longirostris.The first phase includes synthesis of a substance which accumulates later in the peripheral cortical granules. During the second phase, yolk globules appear in the cytoplasm. Immunodiffusion, Immunoelectrophoresis and immunofluorescence demonstrated materials immunologically similar to vitellin in the yolk globules of developed oocytes but not in oocytes in the first phase of development. This material appears also in the subepidermal adipose tissue and in the hemolymph, indicating the extraovarian origin of vitellin.