Histological and Morphometric Characterization of Major Salivary Glands in Iranian Long-eared Hedgehog (Hemiechinus auritus)
Document Type : Original Article
Authors
Department of Basic Sciences, Faculty of Veterinary Medicine, Bu-Ali Sina University, Hamedan, Iran
10.22084/avr.2025.31399.1012
Abstract
The Iranian long-eared hedgehog (Hemiechinus auritus) represents a unique model of mammalian adaptation to arid environments. Despite the critical role of salivary glands in maintaining oral homeostasis and facilitating survival in water-scarce conditions, no histological studies have been conducted on these structures in this species. This pioneering investigation aimed to provide the rst comprehensive histological description and morphometric analysis of the three major salivary glands in H. auritus. In this study, ve deceased adult hedgehogs (3 females, 2 males) were utilized. Following standard necropsy procedures, parotid, submandibular, and sublingual glands were harvested and xed in 10% buffered formalin. Tissues underwent routine histological processing including dehydration through ascending alcohol series, clearing with xylene, and paraffin embedding. Serial sections (5-7 um) were stained with hematoxylin-eosin. Digital image analysis system comprising light microscope (Medic M-107 BN, China), camera (Dino-Lite), imaging software (Dino Capture V.2), and analysis software (Image-Pro Plus v.6) was employed to determine serous/mucous acinar ratios. This descriptive study focused solely on reporting tissue architecture without statistical comparisons. The parotid gland exhibited exclusively serous architecture (100%) with densely packed acini, prominent striated ducts, and minimal interlobular connective tissue. Submandibular glands displayed mixed serous-mucous composition with 77.64% serous and 22.35% mucous acini, featuring well-developed ductal systems and serous demilunes. Sublingual glands were predominantly mucous (75.14%) with scattered serous components (24.83%), characterized by large tubuloacinar units and reduced striated duct density. All glands demonstrated typical mammalian salivary gland organization with distinct capsular investments and lobular architecture. This histological characterization of H. auritus salivary glands reveals sophisticated structural adaptations re ecting the species' xerophilic lifestyle. The serous-dominant parotid facilitates enzymatic digestion of chitinous prey, while the mucous-rich sublingual provides essential mucosal protection against desiccation. The mixed submandibular composition ensures functional versatility. These ndings establish a morphological baseline for future comparative studies and highlight the potential of H. auritus as a model for investigating mammalian adaptations to environmental stress.
Keywords
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Histological and Morphometric Characterization of Major Salivary Glands in Iranian Long-eared Hedgehog
(Hemiechinus auritus): 39{46 44
Anatomy and histology of rodent and human ma-
jor salivary glands-Overview of the japan salivary
gland society-sponsored workshop-. Acta histo-
chemica et cytochemica. 2012;45(5):241-50.
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vary gland adaptations in relation to feeding be-
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2017;4(2):7-13.
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Wang YX, et al. An estimation of Erinaceidae
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bite force production and its relationship to diet
in bats. Funct Ecol. 2010;24(4):776-84.
[17] Shackleford JM, Wilborn WH. Structural and
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ing two desert species. Am J Anat. 1968;122:237-
54.
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ski M, et al. Salivary gland models in experimen-
tal and clinical research: A comparative review.
Frontiers in Physiology. 2019;10:1435.
[19] Tabak LA. In defense of the oral cavity: struc-
ture, biosynthesis, and function of salivary mucins.
Annu Rev Physiol. 1995;57:547-64.
[20] Tandler B, Phillips CJ. Microstructure of mam-
malian salivary glands and its relationship to diet.
In: Garrett JR, Ekstrom J, Anderson LC, editors.
Frontiers of oral biology. Vol. 10. Basel: Karger;
2000. p. 21-35.
[21] Tenovuo JO. Antimicrobial function of human
saliva-how important is it for oral health? Acta
Odontologica Scandinavica. 2002;60(4):202-206.
[22] Terra WR, Ferreira C. Biochemistry and molec-
ular biology of digestion. In: Gilbert LI, editor.
Insect molecular biology and biochemistry. Lon-
don: Academic Press; 2012. p. 365-418.
[23] Ziaie H. A eld guide to the mammals of Iran.
Tehran: Iranian Wildlife Center; 2008. 432 p.
ical and histochemical studies on the major sali-
vary glands of the hedgehog (Atelerix albiventris).
Egypt J Histol. 2020;43(1):37-49.
[2] Akbari G, Kianifard D, Hamidian G, Babaei
M. Major and minor salivary glands in Per-
sian squirrel (Sciurus anomalus): the aspect of
macroanatomy, microanatomy, and histochemical
properties. Zoomorphology. 2024 Aug;143(2):559-
70.
[3] Amano O, Mizobe K, Bando Y, Sakiyama K.
Histological and Morphometric Characterization of Major Salivary Glands in Iranian Long-eared Hedgehog
(Hemiechinus auritus): 39{46 44
Anatomy and histology of rodent and human ma-
jor salivary glands-Overview of the japan salivary
gland society-sponsored workshop-. Acta histo-
chemica et cytochemica. 2012;45(5):241-50.
[4] Corbet GB. The mammals of the Palaearctic re-
gion: a taxonomic review. London: British Mu-
seum (Natural History); 1988. 314 p.
[5] El-Sayyad HI, Mahmoud AM, Hassan MA. Sali-
vary gland adaptations in relation to feeding be-
havior in insectivores. Journal of Zoology Studies.
2017;4(2):7-13.
[6] He K, Chen JH, Gould GC, Yamaguchi N, Ai HS,
Wang YX, et al. An estimation of Erinaceidae
phylogeny: a combined analysis approach. PLoS
One. 2012;7(6):e39304.
[7] Hutterer R. Order Erinaceomorpha. In: Wilson
DE, Reeder DM, editors. Mammal species of the
world: a taxonomic and geographic reference. 3rd
ed. Baltimore: Johns Hopkins University Press;
2005. p. 212-19.
[8] Karami M, Hutterer R, Benda P, Siahsarvie R,
Krystufek B. Annotated check-list of the mam-
mals of Iran. Lynx (Praha). 2008;39(1):63-102.
[9] MacMillen RE. Water regulation in Peromyscus.
Journal of Mammalogy. 1983 Feb 28;64(1):38-47.
[10] Matsuzaki T, Tajika Y, Ablimit A, Aoki T, Hagi-
wara H, Takata K. Aquaporins in the digestive
system. Med Electron Microsc. 2004;37(2):71-80.
[11] Nagato T, Matsumoto K, Tanioka H, Kodama J,
Toh H. Effect of denervation on morphogenesis of
the rat fungiform papilla. Cells Tissues Organs.
1995 Jul 17;153(4):301-9.
[12] Nowak RM. Walker's mammals of the world. 6th
ed. Baltimore: Johns Hopkins University Press;
1999. 1936 p.
[13] Phillips CJ, Tandler B, Nagato T. Evolutionary
divergence of salivary gland acinar cells: a for-
mat for understanding molecular evolution. In:
Garrett JR, Ekstrom J, Anderson LC, editors.
Glandular mechanisms of salivary secretion. Basel:
Karger; 1998. p. 39-51.
[14] Podhorska I. Morphology of salivary glands
in European hedgehog. Folia Morphol (Praha).
1982;30:127-36.
[15] Roberts TJ. The mammals of Pakistan. Oxford:
Oxford University Press; 1997. 525 p.
[16] Santana SE, Dumont ER, Davis JL. Mechanics of
bite force production and its relationship to diet
in bats. Funct Ecol. 2010;24(4):776-84.
[17] Shackleford JM, Wilborn WH. Structural and
functional aspects of rodent salivary glands includ-
ing two desert species. Am J Anat. 1968;122:237-
54.
[18] Szczepanek-Parulska E, Wroblewska M, Szyman-
ski M, et al. Salivary gland models in experimen-
tal and clinical research: A comparative review.
Frontiers in Physiology. 2019;10:1435.
[19] Tabak LA. In defense of the oral cavity: struc-
ture, biosynthesis, and function of salivary mucins.
Annu Rev Physiol. 1995;57:547-64.
[20] Tandler B, Phillips CJ. Microstructure of mam-
malian salivary glands and its relationship to diet.
In: Garrett JR, Ekstrom J, Anderson LC, editors.
Frontiers of oral biology. Vol. 10. Basel: Karger;
2000. p. 21-35.
[21] Tenovuo JO. Antimicrobial function of human
saliva-how important is it for oral health? Acta
Odontologica Scandinavica. 2002;60(4):202-206.
[22] Terra WR, Ferreira C. Biochemistry and molec-
ular biology of digestion. In: Gilbert LI, editor.
Insect molecular biology and biochemistry. Lon-
don: Academic Press; 2012. p. 365-418.
[23] Ziaie H. A eld guide to the mammals of Iran.
Tehran: Iranian Wildlife Center; 2008. 432 p.
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