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Biological Aspects of the Tongue and Oropharyngeal Cavity of the Eurasian Collared Dove (Streptopelia decaocto, Columbiformes, Columbidae): Anatomical, Histochemical, and Ultrastructure Study

Published online by Cambridge University Press:  08 July 2021

Ahmed A. El-Mansi*
Affiliation:
Department of Biology, Faculty of Science, King Khalid University, P.O. Box 641, Abha61421, Saudi Arabia Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt
Eman A. El-Bealy
Affiliation:
Department of Biology, Faculty of Science, King Khalid University, P.O. Box 641, Abha61421, Saudi Arabia
Mohamed A. Al-Kahtani
Affiliation:
Department of Biology, Faculty of Science, King Khalid University, P.O. Box 641, Abha61421, Saudi Arabia
Khalid A. Al-Zailaie
Affiliation:
Department of Biology, Faculty of Science, King Khalid University, P.O. Box 641, Abha61421, Saudi Arabia
Ahmed M. Rady
Affiliation:
Department of Biology, Faculty of Science, King Saud University, Riyadh, Saudi Arabia
Mohamed A. Abumandour
Affiliation:
Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Alexandria University, Behera, Egypt
Dina A. El-Badry
Affiliation:
Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt
*
*Corresponding author: Ahmed El-Mansi, E-mail: [email protected]; [email protected]
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Abstract

We characterized the morphological and anatomical adaptations of the lingual microstructures of the Eurasian collared dove and discussed their implications for its dietary niche. We analyzed tongues of nine S. decaocto using histological, histochemical, stereomicroscopic, and scanning electron microscopic techniques. Our findings showed that the tongue is relatively short with a tapered apex that carries a terminal lingual nail. However, the lingual body has median scales and is bordered laterally by filiform papillae. Further, the tongue body bears a distinctive papillary crest. The tongue root is nonpapillate and infiltered with orifices of the posterior salivary glands. The bulky laryngeal mound has a circular glottic fissure, carrying a single row of papillae at the rear edge. Concurrently, our histological and histochemical findings demonstrate that the tongue has taste buds, anterior and posterior salivary glands, along with an elongated entoglossum that extends from lingual apex to root. Besides, ovoid and globular mucous glands displayed intense alcianophilic reactions. More substantially, the palate is made up of three palatine ridges with a caudal choanal cleft that was bounded by two rows of palatine papillae. Our data indicate multiple and novel structural variations for the lingual and palatal sculptures coopted for their feeding style.

Type
Micrographia
Copyright
Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of the Microscopy Society of America

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