Scanning electron microscopic studies of the lingual papillae in the English horse

Abstract

The purpose of this study was to describe the distribution and surface structure of the lingual papillary system in four male adult English horses by scanning electron microscopy. The animals were supplied from the Jockey Club of Turkey (TJK). Tissue samples were taken from the dorsal, ventral and lateral surface of the apex, corpus and radix of the tongue. Filiform papillae were distributed mainly on the dorsum, being abundant, very long and with a slim cylindrical form with pointed endings or multi-bifurcated terminations at the apex. These papillae were typically conical in shape with a wider base in the corpus of the lingua and absent on the radix of the lingua. Fungiform papillae were mainly on the lateral surfaces and lobulated forms were also observed. The horses have two large vallate papillae, located on the dorsum close to the caudal part of the tongue. These papillae were surrounded by a prominent gustatory groove. The vallate papillae had many taste pores opening into the papillary groove. The foliate papillae were observed just rostral to the palatoglossal arches. These papillae have many variable sized taste pores which open into the grooves between the papillary leaves. The papillary leaves were covered with concentrically arranged cornified cells of variable appearance. However, there were no lingual papillae on the ventral aspect of the horse's tongue.