Is the ileo-caecal Peyer's patch in ruminants a mammalian "bursa-equivalent"?
The ileo-caecal Peyer's patch (IPP) in young ruminants shows prenatal maturation and involution in young age, mainly like the thymus (1, 7, 8). In an examination of three-week-old calves IPP had features compatible with an essentially thymus-independent, primary function, different from that of jejunal patches. Features of IPP included very high lymphoblastic activity despite scarcity of coronal cells and few high endothelial venules in the interfollicular tissue.
D000818:Animals; D001717:Birds; D002060:Bursa of Fabricius / Q000196:embryology / Q000502:physiology*; D002417:Cattle; D006651:Histocytochemistry; D007080:Ileocecal Valve; D007583:Jejunum; D008221:Lymphoid Tissue / Q000502:physiology*; D010581:Peyer's Patches / Q000166:cytology / Q000196:embryology / Q000502:physiology*; D012756:Sheep; D013601:T-Lymphocytes / Q000166:cytology