Not having to masticate its food thoroughly, the deer can fill its paunch rapidly and then retire to a safe place to do the job properly. When the deer is ready, it regurgitates a ball of partially chewed food about the size of an orange and rechews it. From there, it goes into the omasurn, then through the abomasum into the intestines where digestion is completed. Deer do not have a gall bladder on their livers. This allows them to eat vegetation that would kill domestic animals.
Deer are ruminants, meaning they are equipped with a four-chambered stomach.
An interesting characteristic about the ruminant's stomach is that it allows the animal to gather a lot of food at once, then chew, and digest it later. The four chambered stomach is needed to process the large quantities of low nutrient food the deer eat. Depending on the type and abundance of food, the deer can fill its stomach in about one or two hours. When a deer eats, food is moved by the tongue to the back of the mouth, where it is chewed just enough to swallow. The food then passes down the gullet into the stomach.