Stomach
Relatively simple and small due to the act of constant grazing Serves as a mixing chamber and holding reservoir Capacity for 8 – 15 litres. (human 2-4 L), non-elastic It is a simple stomach and bent sharply forming a ‘J’. The stomach is divided into 4 external sections: Cardia – region where the esophagus empties its contents into the stomach Fundus – upper region of the stomach, allows for accumulation of gases produced by digestion. Body – the main central region of the stomach. Pylorus – this lower muscular portion facilitates emptying of stomach contents into the small intestine. The heavy bundles of circular muscle near the cardia form the cardiac sphincter and near the pylorus form the pyloric sphincter. The cardiac sphincter maintains considerable tone, even after the death of the animal. This strong sphincter and the very oblique angle at which the esophagus joins the stomach make it practically impossible for the stomach contents to enter the esophagus. A mucus membrane lines the interior stomach and 2 distinct regions may be differentiated: Non-glandular region –slightly folded; it is whitish, smooth, firm and covered by thick cornified stratified squamous epithelium. Glandular region –forms high but transient folds called rugae . The surface of the mucosa is characterized by tiny openings into the gastric pits. The glandular lining is divided into 3 regions based on the gastric glands it contains cardiac, fundic & pyloric.
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