Histomorphological and Histochemical Study on the Tongue of Black Francolin (Francolinus francolinus)

Histomorphological and histochemical observations of black Francolin tongue. Ten tongues (five males and five females) of adult birds were carried out macroscopically and microscopically. The length and width of tongues were measured. Routine histological staining and special stains for mucin were done. The tongue width but not length showed significantly (p≤0.05) higher in male compared with female. The dorsal surface of the tongue had median groove. At the tongue body-base junction there was single row of backward directed papillae. Double transverse rows of pharyngeal papillae located behind the laryngeal cleft. Hard keratinized plates are covered the ventro-lateral surfaces of the tongue. The dorsal surface of the tongue is covered by parakeratinized stratified sequamous epithelium except the ventro-lateral surface and the lingual papillae. Simple branched tubulo-alveolar lingual salivary glands were occupied the lateral and the base of the tongue. The secretory cells of the Medial group (Mg) of the Anterior lingual glands (Alg) and the posterior lingual glands (Plg) contained large amount of mucin compared with the Lateral group (Lg). The secretions had neutral reaction. However, the weak carboxylated acid mucin is detected in Lg. Meanwhile, both carboxylated and sulphated acid mucin reactions were observed in the Mg of the Alg and the Plg. The histomorphological observation of the male and female black francolin tongue showed no difference.