Histomorphogenesis of Upper Beak in Muscovy Ducks (Cairina moschata)

Abstract

The objective of the present work was to provide information on the histology and morphometry of the upper beak of developmental ages of Muscovy Ducks (Cairina moschata) by using fourty nine healthy post-hatching Muscovy ducks of both sexes ranging from 1-60 days old. The upper beak was a wide spoon-shaped in all examined ages. It measured 19.32 mm at one day old and increased to reach 65.52 mm at 60 days old. At the median part of the tip of upper beak was observed a circumscribed plate shaped like a finger nail, called the nail of the upper beak, its rostral free edge projected rostroventrally beyond the nail of the lower beak. The free tip of the upper beak by SEM contained two transversely curved rows of small dome shaped dermal papillae at one day old. In addition 12-14 transversely curved rows of small papillae were demonstrated behind the dermal papillae at 15 days old. They became 18-20 in numbers at 60 days old. In all examined ages. The ventral parts of the rostrally situating lamellae which located on the lateral edge of the upper beak were directed caudally, but the caudally situating lamellae were vertically directed. The dermis of the upper beak was formed of dense connective tissue containing numerous lamellated sensory corpuscles especially on both sides of the lateral edges of the upper beak.

Keywords

• Histology
• Muscovy Ducks
• SEM
• Upper beak