Some histological studies on the pre-and postnatal development of rabbit gustatory papillae by light and scanning microscopes

ABSTRACT

The gustatory system allows animals to distinguish varieties of food and affects greatly the consumption of food, hence the health and growth of animals. In the current study the morphogenesis of gustatory papillae was investigated in rabbit during fetal and postnatal life by light and scanning electron microscopy. Tongues were obtained from rabbit fetuses starting from the embryonic day [E16] to [E30] and from newborns till maturity. At E16, the first primordial of vallate papillae were observed as epithelial thickenings at the root of the tongue. At E18, the first primordial of fungiform papillae were observed at the posterior margins of the tongue where the Ebner's gland was also observed. By E26, the primitive taste buds of foliate papillae were not found and this might be due to transient degeneration. Mature taste buds of the foliate papillae were then observed by the end of the first week. Meanwhile, mature fungiform papillae were observed at birth and the vallate papillae by the end of the second week while the foliate papillae reached their maturity by the end of the first month. It is concluded that the rudiments of rabbit gustatory papillae appeared at different stages of prenatal development where the vallate papillae appeared first followed by fungiform while foliate papillae were the last to appear. The development of fungiform and vallate papillae occurred mainly during the prenatal period while the development of foliate papillae occurred mainly after birth. The present findings were discussed with previous publications