Owls cannot chew, so their digestive system takes on the process of breaking down the meal. It does so in two parts, with two stomach-like organs. The first is the proventriculus which begins the break-down process with digestive enzymes that filter out the non-digestible materials like fur and feathers, or teeth and bones. The second stomach called the ventriculus or gizzard takes on the mashing process to break the meal down into smaller pieces for the intestines to absorb. The non-digestible materials are held in the gizzard and compressed into a pellet and are sent back up into the proventriculus, and then regurgitated out through the esophagus and mouth. The pellet process may take up to several hours, and prevents the owl from eating additional meals until it is expelled.
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