Gross anatomical histological and certain histochemical studies on the pituitary and pineal gland of goat and sheep

Abstract

The present study was conducted on pituitary and pineal gland of six each from goat and sheep during summer and winter season (total 12 pituitary and 12 pineal gland) to observe gross anatomical, morphometrical, histological and histochemical characteristics. The topographical position and relationship of pituitary and pineal glands were recorded while the glands were in their original positions and then the glands were taken out to record morphometrical parameters. After recording the gross anatomical features the tissue from the pituitary and pineal glands were processed for histological and histochemical studies as per standard protocol of paraffin embedding technique. Paraffin sections were stained by various staining methods to study histoarchitecture and histochemical reactions of pituitary and pineal gland of sheep and goat in summer and winter season. The pituitary gland of goat and sheep was an oval elongated structure situated transversely across hypophyseal fossa. The pituitary gland in both species was an oval, elongated structure located transversely across the hypophyseal fossa, with adenohypophysis forming the major portion. Sheep consistently exhibited significantly greater (p and#8804; 0.05) pituitary weight, length, width, and volume compared to goats, with seasonal effects more pronounced in sheep, showing larger dimensions during summer. Histologically, the pituitary showed distinct zones pars distalis, pars intermedia, and pars nervosa each with characteristic cellular features. The acidophils were rounded to polygonal in shape, with abundant dark eosinophilic cytoplasm and rounded central vesicular nuclei. The basophil cells were oval to polygonal in shape with presence of basophilic cytoplasmic granules. The chromophobe cells were small polygonal cells with scanty amounts of pale cytoplasm and rounded heterochromatic nuclei. Acidophils and basophils of the pars distalis displayed seasonal variations in size and nuclear dimensions, with larger values observed during summer in sheep. The pineal gland