The Histological and Histochemical Structure of the Rectum in the Cockatiel

Abstract

Birds are among the most important vertebrate animals on the surface of the Earth, so they are widely studied in terms of environment, nutrition, reproduction, migration as well as their internal structure. This study aimed to recognize the histological and histochemical structure of the Rectum in Cockatiel Nymphicus hollandicus, which is one of the beautiful ornamental birds that are raised in homes, by using compound optical microscopy and histological and histochemical techniques. The histological results showed that the rectal wall was consisted of four tunica: the mucosa; submucosa; muscularis; and finally serosa. The mucosa formed villi of various shapes extending towards the rectal lumen. These villi is covered with a simple columnar epithelial tissue with a large number of secretory goblet cells, but their spread differs among the villi. Themucosa's lamina propria is composed of loose connective tissue that is rich in blood vessels and also contains intestinal glands or Lieberkuhkn's crypts that appeared and spread below the villi. While the lymph nodes not observed in this bird, and it is one of the striking results. The submucosa is composed of loose connective tissue. In contrast, the muscularis consisting of smooth muscles of two arrangements, theouter longitudinal andinner circular the. As for histochemical results, epithelial tissue cells of both types and secretory cells of the intestinal glands have shown positive responses to histochemical techniques that used, but to varying degrees. The stronger responses have emerged to detect mucous and carbohydrates detection techniques, indicating a widespread of these substances in this organ. The study concluded that the rectal composition in this bird is proportional to its function and the nature of the food it eats and that the materials secreted from its tissues contribute to the completion of this function.