Morphological and histochemical observations of the red jungle fowl tongue Gallus gallus
Morphological and histochemical study of the tongue of ten adult red jungle fowl (RJF), Gallus gallus were carried out at macroscopic and microscopic levels. The tongue was triangular with a wide dorsal and ventrolateral surface with median groove at the rostral part. Between the body and the roots appears a transverse row of the lingual conical papillae which was directed backwards. Behind the laryngeal cleft, there was a single row of pharyngeal papillae. The lingual mucosa showed parakeratinization, while there was a clearly recognizable keratinized band on the ventrolateral surface and the conical papillae. The cell cytoplasm of the medial group (MG) of the anterior lingual glands and the posterior glands contained large amounts of mucin compared with the lateral group (LG). The mucin of the lingual glands contained vicinal diol groups. Moreover, the sulphate containing glycoconjugates indicated in the MG and the posterior glands with a strong acid mucin reaction. Meanwhile, the LG of the anterior lingual glands exhibited carboxylated mucin with weak acid mucin reaction. In conclusion, the differences in the arrangement of the lingual and pharyngeal papillae in the RJF than that in other birds particularly domestic chicken may reflects the changes which occurred for the latter during domestication. The contents of mucins in the medial and lateral groups of the anterior lingual gland were varied, however, no differences histochemistry between the medial group and the posterior lingual gland were observed.
Key words: Lingual salivary glands, mucin reaction, red jungle, tongue.