عنوان مقاله [English]
The morphology of the large intestine in birds is different. In addition to its nutritional role, because of the existence of lymphatic tissue, it plays an important immunological role. The present study was designed and conducted to expand the histological knowledge of the gastrointestinal tract in birds by evaluating the histomorphology of the cecum and colon at different ages. For this purpose, 36 ostrich chicks were selected in 6 age groups. These samples were selected from slaughterhouses around Tehran at the ages of one and fifteen days and one, three, six, and twelve months. In this study, it was found the epithelium of the cecum is pseudostratified and simple columnar, and the number of goblet cells increases with the age of the chickens. The muscularis mucosa at the base of the cecum was indistinct and thin, but clear at the apex of the cecum and colon. The thickness of the muscular layer increased with age the Auerbach plexus were mostly seen between the fibers of the longitudinal layer of the muscular layer. The lymphatic tissue was also observed in follicular shape in the lamina propria of the cecum from the age of six months. Based on the results, it can be concluded that in general, in terms of histomorphological features, the development of the large intestine in ostrich chickens is very similar to other birds, especially the Struthioniformes. However, the differences can be found in the condition of the muscularis mucosa and the distribution and timing of lymphatic tissue formation.