proventriculus

The proventriculus is part of the digestive system of birds. An analogous organ exists in insects and many other invertebrates.

==Birds== The proventriculus is a standard part of avian anatomy and is a rod-shaped organ, located between the esophagus and the gizzard of most birds. It is generally a glandular part of the stomach that may store and/or commence the digestion of food before it progresses to the gizzard. The primary function of the proventriculus is to secrete hydrochloric acid (HCl) and digestive enzymes such as pepsinogen into the digestive compartments that will churn the ingested material through muscular mechanisms.