Histology, histochemistry and ultrastructure of the lymphoid tissue in cloaca were studied in six White Leghorn chickens of three months of age. The lymphoid patches were distributed along the dorsal wall of the proctodeum of cloaca in all the birds. The tunica mucosa of cloacal lymphoid tissue consisted of a simple tall columnar lining epithelium which was modified into a lymphoepithelium. | Histology, histochemistry and ultrastructure of the cloacal lymphoid tissue in white leghorn chicken
