552 Int. J. Morphol., 35(2):552-555, 2017. Comparative Morphometric Study of the Filiform Lingual Pa- pilla in the Middle East Blind Mole Rat (Spalax ehrenbergi, Nehring, 1898) and Wistar Albino Rat Estudio Morfométrico Comparativo de la Papila Lingual Filiforme en la Rata Topo Ciega del Medio Oriente (Spalax ehrenbergi, Nehring, 1898) y la Rata Albino Wistar Zelal Karakoç 1 ; Sennur Ketani 2 ; M. Aydin Ketani 3 & Mehmet Kilinç 4 KARAKOÇ, Z.; KETANI, S.; KETANI, M. A. & KILINÇ, M. Comparative morphometric study of the filiform lingual papilla in the Middle East blind mole rat (Spalax ehrenbergi, Nehring, 1898) and wistar albino rat. Int. J. Morphol., 35(2):552-555, 2017. SUMMARY: This study aimed to reveal the morphometric differences between blind mole rats which live under ground and rats which live under laboratory conditions with regard to the length, base width, keratinization thickness and microscopic papilla depth. For this purpose, 7 adult blind mole rats and 7 adult Wistar albino rats were used in the study. All tongues were removed and fixed in 10 % neutral formalin. 4-5 micrometer of sections were obtained from paraffine sections which were obtained with routine histological follow ups and Crossman's modified triple staining was applied. While papilla length was found as 184.73±26.68 μm, base width 65.46±16.51 μm, keratinization thickness 11.60±1.37 μm, microscopic papilla depth 49.89±8.19 μm in blind rats; these values were found as 177.49±31.44 μm, 50.08±7.57 μm, 13.08±5.32 μm and 89.12±19.31 μm, respectively in rats. While a statistically significant difference was not detected between lengths (p>0.05), the difference between papilla width was found significant (p<0.05). While keratinization was found to be thicker on posterior side compared to anterior side in both species, a difference was not detected between keratinization thickness measurements (p>0.05). The difference between two species with regard to papilla depth was detected to be significant (p<0.001). The finding that papilla depth decreases as base width increases and the difference’s being statistically significant suggested that living in different environments with different humidity could be effective on morphologic structures of the tongue in blind mole rats and rats. KEY WORDS: Blind Mole Rat; Filiform lingual papilla; Morphometry. INTRODUCTION Tongue is an organ which consists specialized skeletal muscle with different morphologic structures work to catch food, keep them, swallowing and grooming hair (Kılınç et al., 2010a). An ample amount of macroscopic papillae are present on dorsal side of the tongue. These papillae are defined as filiform, conical, fungiform, foliate and circumvallate papillae. Filiform papillae are the ones with mechanic effect and do not include taste buds, have connective tissue and covering keratinized squamous epithelium. Filiform structures which are conical and cover dorsal side of the tongue help keeping food within the mouth through increasing friction surface (Iwasaki, 2002; Kılınç et al., 2010b). Tongue plays an important role in feeding together with the intra-oral organs. Tongues of the animals which live in different environments like mammals, poultry, rodents, fish, reptiles, amphibian were analyzed anatomically and histologically under light and electron microscopy in many studies (Kumar et al., 1998; Nishida et al., 2000; Pastor et al., 2008; Nonaka et al., 2008; Harem et al., 2009; Kılınç et al., 2010a; Tütüncü et al., 2012; Reginato et al., 2014; Kuloglu 2016). Previous studies have reported that keratinization degree and magnitude showed significant differences between species and these differences were associated with humidity (Iwasaki). Papillae on the tongue were also 1 Department of Histology and Embryology, Veterinary Medicine Faculty, University of Siirt, Siirt- Turkey. 2 Department of Biology Education, Ziya Gökalp Education Faculty, University of Dicle, Diyarbakır- Turkey. 3 Department of Histology and Embryology, Veterinary Medicine Faculty, University of Dicle, Diyarbakır- Turkey. 4 Department of Anatomy, Veterinary Medicine Faculty, University of Dicle, Diyarbakır- Turkey.