A Comparative Morphological Study On The Pancreas Of The Dromedary And The Donkey

The colour of the pancreas is grayish pink in the camel and reddish cream in the donkey. - The camel pancreas is covered by great amount of fat (14g/171g). - The weight of the pancreas is 171 gm in the camel and 110 gm in the donkey. - The pancreas of the camel and donkey has a complete pancreatic ring through which the portal vein passes. - the left lobe is longer than the right lobe in both the camel and donkey. - The camel and donkey pancreas has only one pancreatic duct (the ventral pancreatic one). - The blood supply of the pancreas of the camel and donkey comes from the hepatic, splenic and cranial mesenteric arteries. - The pancreas of the camel and donkey is covered by connective tissue capsule mainly of collagen fibers and a few elastic fibers. The capsule is also rich inadipose tissue. - The capsule sent connective tissue septa mainly of collagen to the parenchyma dividing it into lobules. 62 - The secretory units of the exocrineportion are tubulo-acinar in the camel, and tubulo-alveolar in the donkey. - Three acinar cells types are reported in the secretory units of the pancreas; active, exhausted, and resting. - The duct system of the exocrine portion is divided into intercalated, intralobular, interlobular and main pancreatic. - The goblet cells are present only inthe ventral pancreatic duct in the donkey pancreas, but none isobserved in the camel pancreas. - The islets of Langerhans appear asa pale area within the secretory units in both camel and donkey pancreas. - The beta cells with spherical nuclei are locatedin the centre of the islets of the camel pancreas, whereas in the donkey are located in the periphery of the islets. - The alpha cells with ovoid nucleiare located in the periphery of the islets of the camel pancreas, butthey are located in the centre of the islets in the donkey pancreas. - The ultrastructure of the acinarand endocrine cells has been studied in the camel pancreas only. 63 - The acinar cell cytoplasm contains a well developed rough endoplasmic reticulum, Golgi complex, round mitochondria, lysosomes and zymogen granules of different shapes and size. - The cytoplasm of the endocrine cells: alpha, beta and delta cells contain round mitochondria, a few rough endoplasmic reticulum, round granules with different electron density and lipid droplets. - The granules of beta cells are lesselectron dense but larger in size than alpha cells; theyhave a distinct halo between the dense material and their limiting membrane. - The granules of alpha cells are highly electron dense and fill their limiting membranes. - The delta cells are smaller in size and less electron dense than both alpha and beta cells. They fill their limiting membranes