Description
The bursa is an epithelial and lymphoid organ that is found only in birds. The bursa develops as a Dorsal diverticulum of the proctadael region of the cloaca. The luminal (interior) surface of the bursa is plicated with as many as 15 primary and 7 secondary plicae or folds. These plicae have hundreds of bursal follicles containing follicle-associated epithelial cells, lymphocytes, macrophages, and plasma cells. Lymphoid stem cells migrate from the fetal liver to the bursa during ontogeny. In the bursa, these stem cells acquire the characteristics of mature, immunocompetent B cells.
The bursa is active in young birds. It atrophies after about six months.
Read more about this topic: Bursa Of Fabricius
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