Ultramorphological studies on the lingual papillae of Rabbit (Oryctolagus cuniculus) in relation to its feeding habits

Abstract

The distribution and structure of the lingual papillae on rabbit tongue were studied in relation toits feeding habits by means of light and scanning electron microscopy. The tongue of rabbit is ofabout 5 cm in length and 9 mm in width. The dorsal surface of the tongue is differentiated intofour regions according to the nature of papillae; apex, body, lingual torus (intermolarprominence) and root. On the surface of the apex and body of the tongue there are four maintypes of papillae: filiform, fungiform, vallate and foliate papillae. The filiform one can bedifferentiated morphologically into five sub types of variable size and shape according to theirlocation. Fungiform papillae are numerous on the anterior part of the tongue. They are ellipticalor circular in shape and embedded in between filiform ones. In this region both filiform andfungiform are devoid of taste buds indicating their mechanoreceptive function. Two oval vallatepapillae with numerous taste buds are situated on the side wall of the tongue root, elucidatingtheir chemoreceptive role. A Pair of patches having well developed foliate papillae is observedin the latero-posterior part of the tongue. Each is oval in shape and has several parallel papillaelacking taste buds and may separate by shallow grooves. Histological observation indicateskeratinization of the dorsal surface of the tongue with variable degrees.