Abstract
The avian gut associated lymphatic tissue (GALT) is very important for understanding the immune response of the digestive system after oral administration of vaccines. This study is carried out on 6 apparently healthy mature pigeons. Two pigeons for gross morphology and the others for histological examination using H&E stain. There are different thickening at the digestive tube, like pharyngeao-esophageal junction, esophageo-proventricular junction and the two rudimentary ceca. The lymphatic tissue is organized in the propria sub mucosa as diffuse lymphatic tissue and lymphatic follicle (nodule). The epithelium in the intestine shows lymphocytic infiltration to form lympho-epithelium. The lymphatic nodules are located not only in the propria-sub mucosa, but also in the tunica muscularis and tunica serosa of the intestine. These GALT function as an integrated mucosal immune system to augment the mechanical and chemical barrier of the surface mucosal epithelium moreover the presence of GALT could play a crucial role in the stimulation of immune system oral vaccination.