Anatomical, Histological, and Immunohistochemical Description of the Abomasum in One-Humped Adult Camel (Camelus dromedary) in the South of Iraq

The camel is an important mammal, especially in the Middle EAST, although it has received less attention than other mammals and ruminants. Due to the lack of studies in this field, the current research was designed to investigate the morphological, histological, and immunohistochemical of one-humped camel's stomach. In this study, the third chamber (abomasum) of the stomach in adult one-humped camels (Camelus dromedaries) were evaluated (n=12). The morphological study of the third chamber showed that it consisted of two parts, the letter J, where the front part was found to be tubular, the outer surface is smooth, swollen, and transparent, while the inner surface has longitudinal folds with a low height. The posterior part is spherical, and the inner surface is divided into two regions. Histological study showed that the abomasum consists of four layers and is lined with simple columnar epithelium. The lamina property is composed of loose connective tissue. It contains different glands that, according to their location from the abomasum, where cardiac, Fundus, and pyloric glands are found, as well as stomach cells such as neck cells, mucous cells, chief cells, and parietal cells. In contrast, the sub mucosa layer is composed of loose connective tissue. It was also observed that the muscular layer is developed and contained from two layers, a circular inner and the outer one is longitudinal. It was also noted that the fourth layer is composed of loose connective tissue. The histochemical study showed a positive response to the PAS reagent.