Because elephants can't digest food effectively, only about 40% of food is used. Intestinal length 1 15 feet (35 meters). The small intestine of an adult is about 12 to 13 feet (3.7 to 4.0 meters) long. When the elephant's intestines weigh 0.9 tons. Elephants excrete an average of 220 pounds (100 kg) of feces every day.