What is bursa of fabricious?

The bursa of Fabricius is a specialized lymphoid organ found in birds, named after the Italian anatomist and embryologist Hieronymus Fabricius ab Aquapendente. It is found at the posterior end of the cloaca and helps to produce B-cells, which are a type of white blood cell involved in the immune response.

During embryonic development, the bursa of Fabricius is one of the first organs to develop in birds, and is responsible for the production of mature B-cells. This organ is unique to birds and plays a vital role in the bird's immune system.

The bursa of Fabricius is most active in young birds, and its function declines as the bird ages. The organ is vulnerable to damage from certain pathogens, such as infectious bursal disease virus, which can lead to a suppressed immune system and decreased B-cell production.

Overall, the bursa of Fabricius is an important part of the avian immune system, responsible for the development and maturation of B-cells necessary for the recognition and elimination of pathogens.