Age related gross and histomorphological studies of thyroid gland in Pati ducks (Anas platyrhynchos domesticus) of Assam

The study was conducted on 42 number of Assam Pati ducks divided into 7 groups to study the gross and histomorphological characteristics of thyroid glands from day-old to 40 weeks of age. The thyroid glands were collected from 6 birds in each group. After recording the gross parameter values the material was fixed and processed for histological studies. The microscopic structure of thyroid glands of Pati ducks revealed primarily the capsule enclosing the follicles that contained colloid in the H & E sections. The interfollicular area contained the parafollicular cells. Parenchyma of thyroid gland was composed of follicles which were separated from each other by interfollicular connective tissue made up of collagen and reticular fibers. A homogenous translucent colloidal mass filled the thyroid follicles in all age groups. C cells were present in the interfollicular zone of the thyroid gland.