SciELO - Scientific Electronic Library Online

vol.76 número4Cryptosporidium infection in non-human hosts in Malawi índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados



Links relacionados

  • Em processo de indexaçãoCitado por Google
  • Em processo de indexaçãoSimilares em Google


Onderstepoort Journal of Veterinary Research

versão On-line ISSN 2219-0635
versão impressa ISSN 0030-2465

Onderstepoort j. vet. res. vol.76 no.4 Pretoria  2009




Morphology of the tongue of the emu (Dromaius novaehollandiae). II. Histological features



M.R. Crole; J.T. Soley

Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria Private Bag X04, Onderstepoort, 0110 South Africa




Although a number of brief, fragmented descriptions have been provided on the gross morphology of the ratite tongue, very few studies have documented the histological structure of this organ. This paper presents the first definitive histological description of the emu tongue and reviews, consolidates and compares the scattered information on the histology of the ratite tongue available in the literature. Five tongues were removed from heads obtained from birds at slaughter and fixed in 10 % neutral buffered formalin. Appropriate longitudinal and transverse segments were removed, routinely processed for light microscopy, and sections examined after staining with H & E and PAS. The entire tongue (body and root) is invested by a non-keratinized stratified squamous epithelium. The supporting connective tissue of the tongue dorsum displays only large, simple branched tubular mucus-secreting glands, whereas the caudal tongue body ventrum and tongue root, in addition to these glands, also exhibits small, simple tubular mucus-secreting glands. Herbst corpuscles are associated with the large, simple branched glands. Lymphoid tissue is restricted to the tongue ventrum and is particularly obvious at the junction of the ventral tongue body and frenulum where a large aggregation of diffuse lymphoid tissue, with nodular tissue proximally, was consistently observed. A structure resembling a taste bud was located in the epithelium on the caudal extremity of the tongue root of one bird. This is the first reported observation of taste buds in ratites. Forming the core of the tongue body is the cartilaginous paraglossum lying dorsal to the partially ossified rostral projection of the basihyale. The histological features of the emu tongue are generally similar to those described for the greater rhea and ostrich, except that taste buds were not identified in these species. The results would suggest that the emu tongue functions as a sensory organ, both for taste and touch (by virtue of taste receptors and Herbst corpuscles, respectively), as well as fulfilling an immunological function.

Keywords: Dromaius novaehollandiae, emu, histology, ratite, tongue



“Full text available only in PDF format”




AL-MANSOUR, M.I. & JARRAR, B.M. 2004. Structure and secretions of the lingual salivary glands of the white-cheeked bulbul, Pycnonotus leucogenys (Pycnontidae). Saudi Journal of Biological Sciences, 11:119-126.         [ Links ]

ANTONY, M. 1920. Über die Speicheldrüsen der Vögel. Zoologische Jahrbücher. Abteilung für Anatomie, 41:547.         [ Links ]

BACHA, W.J. & BACHA, L.M. 2000. Digestive system, in Color atlas of veterinary histology, edited by D. Balado. Philadelphia: Lippincott Williams & Wilkins.         [ Links ]

BAILEY, T.A., MENSAH-BROWN, E.P., SAMOUR, J.H., NALDO, J., LAWRENCE, P. & GARNER, A. 1997. Comparative morphology of the alimentary tract and its glandular derivatives of captive bustards. Journal of Anatomy, 191:387-398.         [ Links ]

BAUMEL, J.J., KING, A.S., BREAZILE, J.E., EVANS, H.E. & VANDEN BERGE, J.C. 1993. Handbook of avian anatomy: Nomina anatomica avium, 2nd ed. Cambridge, Massachusetts: Nuttall Ornithological Club.         [ Links ]

BERKHOUDT, H. 1979. The morphology and distribution of cutaneous mechanoreceptors (Herbst and Grandry corpuscles) in bill and tongue of the mallard (Anas Platyrhynchos L.). Netherlands Journal of Zoology, 30:1-34.         [ Links ]

BERKHOUDT, H. 1985. Structure and function of avian taste buds, in Form and function in birds, Vol. 3, edited by A.S. King & J. McLelland. London: Academic Press.         [ Links ]

BONGA TOMLINSON, C.A. 2000. Feeding in paleognathous birds, in Feeding: form, function, and evolution in tetrapod vertebrates, edited by K. Schwenk. San Diego: Academic Press.         [ Links ]

BOTEZAT, E. 1910. Morphologie, Physiologie und phylogenetische Bedeutung der Geschmacksorgane der Vögel. Anatomischer Anzeiger, 36:428-461.         [ Links ]

BRADLEY, O.C. 1915. The structure of the fowl. London: A. and C. Black, Ltd.         [ Links ]

CALHOUN, M.L. 1954. Microscopic anatomy of the digestive system of the chicken. Ames, Iowa: Iowa State College Press.         [ Links ]

CHO, P., BROWN, B. & ANDERSON, M. 1984. Comparative gross anatomy of ratites. Zoo Biology, 3:133-144.         [ Links ]

CROLE, M.R. & SOLEY, J.T. 2008. Histological structure of the tongue of the emu (Dromaius novaehollandiae). Proceedings of the Microscopy Society of Southern Africa, 38:63.         [ Links ]

CROLE, M.R. & SOLEY, J.T. 2009. Morphology of the tongue of the emu (Dromaius novaehollandiae). I. Gross anatomical features and topography. Onderstepoort Journal of Veterinary Research 76:335-345.         [ Links ]

CUVIER, G. 1836. Leçons d'anatomie comparée, 3rd ed. Vol. 1 & 2, edited by M. Duméril. Bruxelles: Dumont.         [ Links ]

DUERDEN, J.E. 1912. Experiments with ostriches. XVIII. The anatomy and physiology of the ostrich. A. The external characters. Agricultural Journal of the Union of South Africa, 3: 1-27.         [ Links ]

FARAGGIANA, R. 1933. Sulla morfologia della lingua e del rialzo laringeo di alcune specie di uccelli Ratiti e Carenati non comuni. Bollettino dei Musei di Zoologia e Anatomia comparata, 43:313-323.         [ Links ]

FEDER, F-H. 1972. Zur mikroskopischen Anatomie des Verdauungsapparates beim Nandu (Rhea americana). Anatomischer Anzeiger, 132:250-265.         [ Links ]

FOWLER, M.E. 1991. Comparative clinical anatomy of ratites. Journal of Zoo and Wildlife Medicine, 22:204-227.         [ Links ]

GADOW, H. 1879. Versuch einer vergleichenden Anatomie des Verdauungssystemes der Vögel. Jenaische Zeitschrift für Medizin und Naturwissenschaft, 13:92-171.         [ Links ]

GARDNER, L.L. 1926. The adaptive modifications and the taxonomic value of the tongue in birds. Proceedings of the United States National Museum, 67: Article 19.         [ Links ]

GARDNER, L.L. 1927. On the tongue in birds. Ibis, 3:185-196.         [ Links ]

GARGIULO, A.M., LORVIK, S., CECCARELLI, P. & PEDINI, V. 1991. Histological and histochemical studies on the chicken lingual glands. British Poultry Science, 32:693-702.         [ Links ]

GENTLE, M.J. 1971a. Taste and its importance to the domestic chicken. British Poultry Science, 12:77-86.         [ Links ]

GENTLE, M.J. 1971b. The lingual taste buds of Gallus domesticus. British Poultry Science, 12:245-248.         [ Links ]

GÖPPERT, E. 1903. Die Bedeutung der Zunge für den sekundären Gaumen und den Ductus nasopharyngeus. Morphologisches Jahrbuch, 31:311-359.         [ Links ]

GOTTSCHALDT, K-M. 1985. Structure and function of avian somatosensory receptors, in Form and function in birds, Vol. 3, edited by A.S. King & J. McLelland. London: Academic Press.         [ Links ]

GUSSEKLOO, S.W.S. & BOUT, G.R. 2005. The kinematics of feeding and drinking in palaeognathous birds in relation to cranial morphology. Journal of Experimental Biology, 208: 3395-3407.         [ Links ]

HARRISON, J.G. 1964. Tongue, in A new dictionary of birds, edited by A.L. Thomson. London: Nelson.         [ Links ]

HODGES, R.D. 1974. The digestive system, in The histology of the fowl. London: Academic Press.         [ Links ]

HOMBERGER, D.G. & MEYERS, R. 1989. Morphology of the lingual apparatus of the domestic chicken Gallus gallus, with special attention to the structure of the fasciae. American Journal of Anatomy, 186:217-257.         [ Links ]

IWASAKI, S. 2002. Evolution of the structure and function of the vertebrate tongue. Journal of Anatomy, 201:1-13.         [ Links ]

JACKOWIAK, H. & GODYNICKI, S. 2005. Light and scanning electron microscopic study of the tongue in the white tailed eagle (Haliaeetus albicilla, Accipitiridae, Aves). Annals of Anatomy, 187:251-259.         [ Links ]

JACKOWIAK, H. & LUDWIG, M. 2008. Light and scanning electron microscopic study of the structure of the ostrich (Strutio camelus) tongue. Zoological Science, 25:188-194.         [ Links ]

KING, A.S. & McLELLAND, J. 1984. Digestive system, in Birds- their structure and function, 2nd ed. London: Bailliere Tindall.         [ Links ]

KOBAYASHI, K., KUMAKURA, M., YOSHIMURA, K., INATOMI, M. & ASAMI, T. 1998. Fine structure of the tongue and lingual papillae of the penguin. Archivum Histologicum Cytologicum, 61:37-46.         [ Links ]

KOCH, T. 1973. Splanchnology, in Anatomy of the chicken and domestic birds, edited by B.H. Skold & L. DeVries. Ames, Iowa: The Iowa State University Press.         [ Links ]

LILLIE, F.R. 1908. The development of the chick. New York: Henry Holt and Co.         [ Links ]

LIMAN, N., BAYRAM, G. & KOÇAK, M. 2001. Histological and histochemical studies on the lingual, preglottal and laryngeal salivary glands of the Japanese quail (Coturnix coturnix japonica) at the post-hatching period. Anatomia, 30:367-373.         [ Links ]

LINDENMAIER, P. & KARE, M.R. 1959. The taste end-organs of the chicken. Poultry Science, 38:545-549.         [ Links ]

MACALISTER, A. 1864. On the anatomy of the ostrich (Struthio camelus). Proceedings of the Royal Irish Academy, 9:1-24.         [ Links ]

McCANN, C. 1973. The tongues of kiwis. Notornis, 20:123-127.         [ Links ]

M CLELLAND, J. 1975. Aves digestive system, in Sisson and Grossman's The anatomy of the domestic animals, edited by R. Getty. Philadelphia: W.B. Saunders Company.         [ Links ]

MCLELLAND, J. 1979. Digestive system, in Form and function in birds, Vol. 1 , edited by A.S. King & J. McLelland. London: Academic Press.         [ Links ]

MCLELLAND, J. 1990. Digestive system, in A colour atlas of avian anatomy. Aylesbury, England: Wolfe Publishing Ltd.         [ Links ]

MCLELLAND, J. 1993. Apparatus digestorius [Systema alimentarium], in Handbook of avian anatomy: Nomina anatomica avium, 2nd ed., edited by J.J. Baumel, A.S. King, J.E. Breazile, H.E. Evans & J.C. Vanden Berge. Cambridge, Massachusetts: Nuttall Ornithological Club.

McMANUS, J.F.A. 1946. Histological demonstration of mucin after periodic acid. Nature (London), 158:202.         [ Links ]

MECKEL, J.F. 1829. System der vergleichenden Anatomie. Halle: Der Rehgerschen Buchhandlung.         [ Links ]

MOORE, D.A. & ELLIOTT, R. 1946. Numerical and regional distribution of taste buds on the tongue of the bird. Journal of Comparative Neurology, 84:119-131.         [ Links ]

NICKEL, R., SCHUMMER, A. & SEIFERLE, E. 1977. Digestive system, in Anatomy of the domestic birds. Berlin: Verlag Paul Parey.         [ Links ]

OWEN, R. 1879. Memoirs on the extinct and wingless birds of New Zealand; with an appendix of those of England, Australia, Newfoundland, Mauritius and Rodriguez, Vol. 1. London: John van Voorst.         [ Links ]

PORCHESCU, G. 2007. Comparative morphology of the digestive tract of the black African ostrich, hen and turkey. Ph.D. thesis, Agrarian State University of Moldova.         [ Links ]

PYCRAFT, W.P. 1900. On the morphology and phylogeny of the palaeognathae (Ratitae and Crypturi) and neognathae (Carinatae). Transactions of the Zoological Society of London, 15:149-290.         [ Links ]

ROACH, R.W. 1952. Notes on the New Zealand kiwis (1). New Zealand Veterinary Journal, 1:38-39.         [ Links ]

ROSE, M.E. 1981. Lymphatic system, in Form and function in birds, Vol. 2, edited by A.S. King & J. McLelland. London: Academic Press.         [ Links ]

SAMAR, M.E., AVILA, R.E., DE FABRO, S.P., PORFIRIO, V., ESTEBAN, F.J., PEDROSA, J.A. & PEINADO, M.A. 1999. Histochemical study of Magellanic penguin (Spheniscus magellanicus) minor salivary glands during postnatal growth. Anatomical Record, 254:298-306.         [ Links ]

TABAK, L., LEVINE, M., MANDEL, I. & ELLISON, S. 1982. Role of salivary mucins in the protection of the oral cavity. Journal of Oral Pathology, 11:1-17.         [ Links ]

TIVANE, C. 2008. A morphological study of the oropharynx and oesophagus of the ostrich (Struthio camelus). M.Sc. dissertation, University of Pretoria.         [ Links ]

TUCKER, R. 1958. Taxonomy of the salivary glands of vertebrates. Systematic Zoology, 7:74-83.         [ Links ]

WARNER, R.L., McFARLAND, L.Z. & WILSON, W.O. 1967. Microanatomy of the upper digestive tract of the Japanese quail. American Journal of Veterinary Research, 28:1537-1548.         [ Links ]

ZISWILER, V. & FARNER, D.S. 1972. Digestion and the digestive system, in Avian biology, edited by D.S. Farner, J.R. King & K.C. Parkes. New York: Academic Press.         [ Links ]



Accepted for publication 20 March 2009-Editor



* Author to whom correspondence is be directed. E-mail:

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons