Anatomical and histological studies of the pyloric caeca in beluga (Huso huso)

Objective: The aim of this study was to determine histologic structure of pyloric caeca in 15-month old Huso huso. Method & Materials: In this study, seven 15-month old Huso huso were induced. After autopsy the mass attached to the end of stomach was removed and fixated in 10% formalin for one week. Then specimens were cut into 0.5 cm pieces, dehydrated, embedded in paraffin and 6 μm sections were prepared, stained with Hematoxylin and Eosin (H&E) and Maldonado methods. Then sections studied under light microscope. Results & Conclusion: In this study, it was shown that pyloric caeca in Huso huso was a fairly large mass that was covered by a thick smooth muscle capsule. There were few fibers of connective cells between muscular cells. Thin smooth muscle lamella was departed from the capsule and penetrated into the organ and made a lot of lobules. Histologic survey indicated that there were many solci in each lobule. Each solcus was surrounded by evident villi. In dorsal ends, some solci were attached together and in there were a great number of smooth muscle cells in the attachment sites. The epithelium on solci and villi were simple cylindrical cells. Between these cells a large amount of mucosal cells were observed. It was indicated that in Huso huso like other sturgeon fish pyloric caeca was a large mass and with one duct connected to the intestine.