Histogenesis of the adrenal gland in Japanese quail (Coturnix coturnix japonica)

The adrenal gland of Japanese quail was derived from the ectoderm and mesoderm. The cortical anlagen of the gland appeared from the peritoneal epithelium and interrenal blastemal cells of the mesonephros on the third and fourth day of incubation. The primordial cells of the adrenal medulla migrated from the prevertebral nerve plexus of the neural crest ectoderm towards the cortical mass on the fourth day. Cord like arrangement of the cortical cells in between sinusoids and cell differentiation started from seventh to tenth day of incubation. Invasion of the medullary cells into the cortical mass was noticed by eigth day of incubation. Vascularisation and encapsulaton of the gland was complete by ten day. Medullary cells were distributed in small islets. There was gradual, increase in proportion of cortical cells and medullary cells from 12 to 15 days of incubation. Differentiation of the adrenaline and noradrenaline cells was observed by 15 day of incubation.