Histological and histochemical studies of parathyroid gland in one-humped camel (Camelus dromedarus)
Thirty one-humped camels were grouped into three: juvenile (Group A), adult (Group B), and old ages (Group C), were used for the study. The camel parathyroid gland tissues were obtained from camels slaughtered at the Kano Metropolitan abattoir. The glands were prepared for standard histological study using haematoxylin and eosin (H and E) stains for light microscopy. For histochemical studies, Periodic Acid Schiff (PAS) special stain was used to demonstrate glycogen and glycoprotein. The results showed that the parathyroid glands are surrounded by a thin capsule of connective tissue. They have abundant stroma of connective tissue, with large smooth muscles all over. The tissue of the parathyroid gland consists of clusters of principal or chief cells. There are two different functional stages of the principal cell. The light principal cell has a large, pale nucleus and pale cytoplasm (described as inactive). The dark principal cell is a smaller cell, with a small, dark nucleus and a dark cytoplasm (active cell). The presence of oxyphil cells was observed. Histochemical studies showed that the tissue of the parathyroid gland in one-humped camel reacted negatively to the Periodic Acid Schiff (PAS) stain. The parathyroid gland consisted of densely packed chief cells (light and dark cells), oxyphil cells, and abundance of adipose cells in the adult male and female. These cells were absent in the younger group, which is generally identical to what is found, specifically, in cows, goats, and in humans, which signifies that one-humped camel can be introduced as an experimental research animal model for human parathyroid gland, in understanding the etiology and possible solution to human parathyroid diseases and osteoporosis. The study of parthyroid gland will enhance the provision of basic and clinical information on endocrinology and related research fields, such as animal breeding and biotechnology in one humped camel.
Keywords: Endocrinology, Histochemistry, Parathyroid gland, Principal (chief) cells, One-humped camel