Macroscopic and microscopic study of the tongue of the aardvark (Orycteropus afer, Orycteropodidae).

Abstract

The aim of this study was to describe the morphology of the tongue in the aardvark (Orycteropus afer). The tongues from one adult and one three-week old aardvark females and one neonate aardvark were studied. The tongue was elongated in the adult and young aardvarks and had a triangular apex in the rostral part of the tongue. Its dorsal surface was covered by numerous papillae divided into mechanical papillae, present in the form of abundant conical or drop-like filiform papillae, and taste papillae in the form of numerous fungiform papillae and three vallate papillae arranged in a V-shape in the caudal part of the tongue (one papilla was located centrally and caudally with respect to the remaining two papillae). The vallate papillae were round with conical pseudopapillae on their surface. They were surrounded by an annular pad, which was formed by filiform papillae with conical tip. Numerous openings of barrel-shaped taste buds were present in the epithelium covering the surface of fungiform papillae, and in the epithelium of inner walls of the vallate papillae. The serous von Ebner`s glands were located beneath the vallate papillae. The mucoserous Weber`s glands were PAS, AB pH2.5, pH1.0 and AB/PAS positive and HDI-weakly positive.