The present investigation examined the pancreas of two types of dove species, African collared dove (Streptopelia roseogrisae) and laughing dove (Streptopelia senegalensis). Histologically, there are no differences between the exocrine and endocrine portions of pancreas of the two species of dove. The exocrine portion consists of acini; the pancreatic acini are spherical or oval in shape and held together by thin connective tissue fibres. The endocrine portion of the pancreas (islets of Langerhans) of the two species of dove contains two distinct types, the large alpha islets type (consisting mostly of alpha and delta cells), and the small beta islets (containing of beta, delta and sometimes alpha cells). While ultrastructurally, there are somewhat few differences found in the exocrine portion of the both species, the exocrine portion of the pancreas consists of zymogenic cells; two types of zymogenic cells are distinguished, dark acinar cells and light acinar cells. In S. roseogrisae, the dark acinar cells are numerous, while in S. senegalensis, they are fewer. The endocrine pancreas contains three types of cells, α, β, and δ cells, and no differences were found between S. roseogrisae and S. senegalensis regarding these three types of cells. The histochemical studies demonstrated the content of polysaccharide materials is similar in the two species of dove, while the protein contents in the acinar and islets cells of S. roseogrisae are stronger than in S. senegalensis. The variability in the density of these materials in the pancreas of the two investigated species may be related to the nature of the nutritive material and habitat or probably to certain biochemical aspects that are controlled by genetic criteria.
Key words: Dove, Histology, Pancreas, Ultrastructure, Histochemistry
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