This study was carried out on 50 embryos and fe- tuses and 40 pars nervosa of the post natal buffalos at various ages to clear out the development of the pars nervosa. The primordial of the pars nervosa was appeared at 15mm CVRL, as evagination from the brain behind the optic chiasma.
It increased in size and surrounded by the pars intermedia of the adenohypophysis. The pituicytes appeared at 60mm CVRL, and increased in size and characterized by large ovoid centrally located nuclei and eosinophilic cytoplasm with cytoplasmic process that extended to made synapse with the nerve fi- bers. The nerve fiber of the hypothalamic hypophy- seal tract was appeared at 120mm CVRL as fine nerve fibers extended in the pars nervosa and between the pituicytes.
Neurosecretory dilatation was appeared at 180 mm CVRL as, dark basophilic ovoid to circular bod- ies between the pituicytes with numerous basophilic granules were appeared in the contour of the herring bodies. The numbers of the herring bodies were decreased with the age advance especially in the post natal life.