The present study was carried out to determine the development of pancreas in ostrich embryo. For this purpose ostrich embryos obtained on 10, 13, 16, 22, 26, 30 and 36 days of prehatching and 1 day of post hatching life. The specimens were stained with haematoxylin eosin [H&E], Gomori and Toluidine blue, and then were explored by light microscopy. The Results showed the primitive pancreas near the liver and duodenum on day 13. Histological observations showed that the pancreas was consisted of undifferentiated epithelial cells, connective tissue, non -organized ducts and bloodvessels. On day 16, pancreas was composed of two dorsal and ventral lobes with the same structure of day 13. The zymogen granules were evident in developed acini on day 22. By aging the level ofconnective tissue and ducts were decreased and the acinar cells were increased. Pancreatic islets were determined on the day 1 after hatching.

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