Immunohistochemical Study on Glucagon-Like Peptide-1(GLP-1) and Pituitary Adenylate Cyclase Activating Peptide (PACAP) in the Small Intestine of Muscovy Duck during the Prehatching and Posthatching Periods

Abstract

The distributions and frequencies of some endocrine cells in the small intestine of Muscovy duck during development were studied with immunohistochemical method using two types of antisera against Glucagon-like peptide-1(GLP-1) and Pituitary adenylate cyclase activating peptide (PACAP). In the small intestine, GLP-1 was first observed in the jejunum at E24 and in the duodenum at E30. However PACAP labeled fibers were first noted in the jejunum and the ileum at E30. The density of GLP-1immunoreactive cells reached the peak at hatch in the duodenum, while in the jejunum and ileum got the peak at 2d (P<0.05). The density of PACAP positive cells reached the peak in the jejunum and ileum at hatch and in the proximal duodenum at 2d and in the distal duodenum at 9d (P<0.05). The distribution of different endocrine cell type in the small intestine exhibit some particularities in the Muscovy duckling. These results can represent an useful information for future physiological investigations that will explore the exact role of PACAP and GLP-1 in the avian intestine during a critical period like the prehatch and posthatch.

Keywords

• glp-1
• immunoreactivity
• muscovy ducklings
• pacap