Anatomical and histological study of thyroid gland in female local donkeys (Eqws africanus asinus) at Basrah city

Abstract

Thyroid gland is an endocrine gland that influences many organs of the body and play an important role in the metabolism of animals and another species. Thyroid gland of female donkeys was situated in the interior part of neck inferior to the larynx. It consist of two lobes were connected by isthmus. The mean and SD of length, width, and thickness in right lobe was 25.66±0.41mm, 21.31±0.59mm, 8.51±0.009mm, while in the left lobe it was 23.15±o.16 mm. 19.65±o.22mm, 8.42±0.19mm respectively. Histologically, the thyroid gland surrounded by connective tissue capsule and contained follicles, follicular epithelium, and parafollicular cells. The follicles filled with colloid.