Ciliated Foregut Cyst of the Proventriculus in a Broiler Chicken

Abstract

A 44-day-old broiler chicken with a ciliated foregut cyst (CFC) of the proventriculus was obtained for pathological investigation. The ellipsoidal cyst, measuring 64 mm in the greatest dimension, was closely attached to the dorsal walls of the proventriculus and the distal part of the esophagus, predominantly to the former organ. The cyst was unilocular with a generally smooth internal surface and filled with pale yellow mucus. Histopathologically, the cystic wall consisted of lining epithelia, subepithelial connective tissue, smooth muscular layers and fibrous capsule. The lining epithelia were composed of pseudostratified ciliated columnar epithelia with occasional goblet cells and a single layer of non-ciliated epithelia. Compound tubular glands were present between the smooth muscular layers. The proventricular mucosa was suggested as an origin of the non-ciliated epithelia and compound tubular glands. Namely, because a common developmental origin of the pseudostratified ciliated columnar epithelia and proventricular mucosa lining the examined cyst is the embryologic foregut from which the anlages of bronchus, esophagus and proventriculus derive, the cyst was diagnosed as CFC. This is the first report of a CFC of the proventriculus in a chicken.