Comparative Gross Morphological Study on the Pituitary Glands of Pig (sus scrofa domestica) and Goat (Capra hircus)

Abstract

The pituitary gland (hypophysis cerebri) plays a central role in regulating growth, metabolism, reproduction, and homeostasis through its endocrine functions. The present study was undertaken to comparatively evaluate the gross morphology and morphometry of the pituitary gland in pigs and goats. The study was conducted on eight adult Large White Yorkshire crossbred pigs and six adult goats. Following careful dissection, the pituitary glands were examined for their location, relations, external morphology, lobation and biometric parameters. In both species, the pituitary gland was located on the ventral aspect of the diencephalon within the sella turcica and  connected to the hypothalamus by the infundibular stalk. However, distinct species-specific differences were observed. The diaphragma sellae was incomplete with a large central aperture in pigs, whereas it was complete with a minute opening in goats. Externally, the gland was irregularly triangular in pigs and elongated oval to pyriform in goats. Sagittal sections revealed clear lobation of the adenohypophysis and neurohypophysis in both species, with more prominent hypophyseal cleft and compact lobation in goats. Morphometric analysis showed that width, thickness, volume, and weight of the pituitary gland were significantly greater in pigs compared to goats (P < 0.01), while length did not differ significantly. These findings demonstrate marked species-specific variations in pituitary morphology and morphometry, providing valuable baseline data for comparative anatomy and endocrinological studies in domestic animals.