bursa of Fabricius

(redirected from bursas of Fabricius)
Also found in: Dictionary, Encyclopedia.

bursa

 [bur´sah] (pl. bur´sae) (L.)
a small fluid-filled sac or saclike cavity situated in places in tissues where friction would otherwise occur. adj., adj bur´sal. Bursae function to facilitate the gliding of muscles or tendons over bony or ligamentous surfaces. They are numerous and are found throughout the body; the most important are located at the shoulder, elbow, knee, and hip. Inflammation of a bursa is known as bursitis.
bursa of Fabricius an epithelial outgrowth of the cloaca in chick embryos, which develops in a manner similar to that of the thymus in mammals, atrophying after 5 or 6 months and persisting as a fibrous remnant in sexually mature birds. It contains lymphoid follicles, and before involution is a site of formation of B-lymphocytes associated with humoral immunity.
bursa muco´sa (mucous bursa) (synovial bursa) a closed synovial sac interposed between surfaces that glide upon each other; it may be subcutaneous, submuscular, subfascial, or subtendinous in location.
subacromial bursa one between the acromion and the insertion of the supraspinatus muscle, extending between the deltoid and the greater tubercle of the humerus. See illustration.
Subacromial bursa, lying between the acromion and supraspinatus tendon and extending between the deltoid and greater tubercle. From Dorland's, 2000.

bur·sa fa·bri·c'i·i

the bursa of Fabricius in poultry, a blind saclike structure located on the posterodorsal wall of the cloaca; it performs a thymuslike function.
Synonym(s): bursa of Fabricius

bursa of Fabricius

(fə-brĭsh′ē-əs, -brĭsh′əs)
n.
A lymphoid gland in birds that is connected to the cloaca and is the site of B cell maturation.

bursa of Fabricius

Lymphoid tissue at the junction of the cloaca and the gut in birds, which gives rise to B lymphocytes.

bursa of Fabricius

An organ in the cloacal-hind gut junction birds found to be important in the maturation of B lymphocytes (B for bursa). The equivalent in humans is probably the tonsils or lymphoid tissue in the intestine.

Fabricius,

Girolamo (Hieronymus ab Aquapendente), Italian anatomist and embryologist, 1537-1619.
bursa fabricii - in poultry, a blind saclike structure located on the posterodorsal wall of the cloaca. Synonym(s): bursa of Fabricius
bursa of Fabricius - Synonym(s): bursa fabricii
Fabricius ship - the outlines of the sphenoid, occipital, and frontal bones, from their fancied resemblance to the hull of a ship.