Investigations on the light and scanning electron microscopic structure of the lingual papillae in the angora goat (Capra hircus): II. Mechanical papillae.

Abstract

This study was conducted to examine the light microscopy (LM) and scanning electron microscopic (SEM) structures of mechanical papillae on the tongue in the Angora goat (Capra hircus). As study materials, the tongues of four adult female Angora goats were used. The samples were collected from the dorsal surfaces of the apex, body, root and torus of the tongue and the ventral surfaces of the lingual apex for light and scanning electron microscopic examinations. Three types of mechanical papillae were seen in Angora goat tongue: papilla filiformes, papilla lentiformes and papilla conicae.The filiform papillae were detected in the dorsal surface of the tongue from lingual apex to lingual torus, and in the ventro-lateral of the lingual apex and on both sides of the lingual torus. The morphological differences were observed in filiform papillae according to their location in the tongue. The lenticular papillae settled on the centre of the lingual torus. Two types of these papillae, irregular-round and pyramid-shaped were identified. The conical papillae were scattered all over the lingual torus, except for the central part and were also seen on the root of the tongue. In the light microscopic examination, it was found that mechanical papillae had a stratified squamous epithelium and a varying degree of keratin layer on epithelial surfaces. In this study, by examining the light and scanning electron microscopic structure of the mechanical papillae in the Angora goat tongue, their similarities and differences with other domestic and wild ruminant species were determined.