Gastrointestinal Tract Duplication Cysts in Thirteen Broiler Chickens

Abstract

Thirteen broiler chickens with gastrointestinal tract duplication cysts, 44 to 49 days of age, were subjected to pathological investigation. In seven cases, the ellipsoidal cysts, measuring 28 to 70 mm in the greatest dimension, were closely attached to the distal ascending part of the duodenum and in three cases they were attached to the proventriculus. In one case the cyst was attached to the esophagus, in one case the cyst was attached to the jejunum and in one case it was attached to the mesenterium. Each cyst was unilocular and non-communicating and its lumina was filled with pale mucus. Histologically, all cystic walls consisted of lining epithelia similar to the intestinal mucosal lining, lamina propria, three layers of smooth muscular tissues and capsules. All cysts and digestive tracts possessed their own smooth muscular tissues. The lining epithelia formed significantly tall villous projections in the cysts closely attached to the duodenum. The results suggest that avian gastrointestinal tract duplication cysts predominantly possess their own smooth muscular tissues, and duodenal duplication cysts are characterized by attachment to the distal ascending part and formation of tall villous projections due to lining epithelia.