The Tongue Dorsal Surface in Fish: A Comparison Among Three Farmed Species

The oral cavity of vertebrates has a very important role in many functions strictly related to the food processing. Two species, sea bass Dicentrarchus labrax and seabream Sparus aurata, are mainly involved in the aquaculture industry in the mediterranean area, moreover the white seabream Diplodus sargus sargus was recently chosen as the best candidate for the diversification of species of commercial interest. The present investigation was carried out, using the standard procedures for light and scanning electron microscopy, to analyze the morphology of the tongue dorsal surface in order to show if relationships are present between the tongue morphology and the nutritional choices of these species. In all the three investigated species three different areas were observed on the dorsal lingual surface: an apex, a body and a root. In the sea bass Dicentrarchus labrax numerous canine-like teeth, organized in pads, were present along the dorsal surface. The presence of numerous taste buds, scattered on the tongue, was showed. In the seabream Sparus aurata the apical part of the tongue is inserted in a pouch with a characteristic medial ridge on the body surface. Numerous taste buds were scattered on the whole surface In the white seabream Diplodus sargus sargus a pouch partially covering the apex was clearly observed. In the pouch, filiform-like and foliate-like papillae can be distinguished. The results show the important role of the fish tongue in the food ingestion process, demonstrating the interaction of food processing, taste and morphological characteristics.