Presence of the Parafollicular Cells in the Thyroid Gland of the One-Humped Camel

The thyroid is an important endocrine gland that affects many organs of the body. A limited number of works have been done on the morphological and histological characteristics of this gland in the camel and controversial debates have been made on the presence of parafollicular cells. The aim of this study is to investigate the histological structure of the thyroid in the camel and determine the presence of parafollicular cells in this gland. This study was performed on 20 camels. The histological structure of the thyroid was studied using light microscope after preparing sections and staining it with Hematoxylin & Eosin, Verhoeff, and Toluidine blue. Thyroid gland has follicles of different sizes, follicular and parafollicular cells, and according to our results these cells are forming about 59.1% and 5% of the gland volume respectively. The large follicles are located in the peripheral part of the gland while the small follicles are seen in the central part of the gland. The central parts of the gland have a more extensive vascular bed than the peripheral parts. This study revealed that the thyroid gland in camel has parafollicular cells, but most of them are present in the central part of the gland.

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