One. Pigs have a relatively large stomach, which is structurally unicompartmental, and the digestive organs are the mouth, pharynx, esophagus, stomach, small intestine (duodenum, jejunum, ileum), large intestine (cecum, colon, rectum), anus, pancreas, liver, and gallbladder. Pigs are vertebrates, mammals, domestic animals, ancient omnivorous mammals. It is categorized into domestic pigs and wild boars. The pig is generally considered to be a shortened form of the family Porcidae. Pigs vary in physical characteristics depending on the breed. But usually large ears, long head, straight nose, narrow waist and back as the main physical characteristics. The hair is coarse and hard, and depending on the breed, it is divided into white, pink, black, brown and fancy colors. Some animals like camels, deer, giraffes, alpacas, antelopes, cows, and sheep will have four stomachs. Because all such animals have complex ruminant stomachs that regurgitate food, they are also known as ruminants.