Abstract
The current study was carried out to investigate both morphological and histochemical features of pineal gland in goat. Eight samples of pineal glands were used. The morphological study was involved the position, relation, weight, length and width of the glands. The tissue sections were prepared for paraffin embedding technique and stained with Hematoxyline & Eosin, Masson trichrom, Alizarin and PAS stains. The morphological result of pineal showed slightly irregular round-spherical shaped, grayish white in color. It located in the same mid-depression between the thalami body and two colliculi. The weight of gland was 0.478±0.02 mg and measured 2.10±0.06mm in length and 2.52±0.15mm in width. Histologically, the pineal gland has enveloped by a smooth thin layer of loose connective tissue capsule showed less trabiculae that carried the blood vessels into gland and the trabiculae have composed of fine collagen fibers. The glandular parenchyma showed marked lobular pattern of division with marked lighter central region which showed less cellular population. The glandular lobule consisted of three types of cells; Type I pinealocytes or dark pinealocytes, the second type was the less populated type II pinealocytes or light pinealocytes and the third type was the glial cell. The Alizarin stain was revealed multiple of variable size calcium patches within collagen fibers. The cytoplasmic contents of both pinealocytes types I & II showed no glycogen granules.