Comparative Histological Architecture of the Glandular Stomach in Sciurus anomalus and Urva auropunctata

Rafal Ayad  Mahdi; Sura Abdul Munaff  Abdul Wahab

doi:10.30526/39.2.4278

Authors

Rafal Ayad Mahdi Department of biology, College of Science, University of Baghdad, Iraq https://orcid.org/0009-0004-2680-8072
Sura Abdul Munaff Abdul Wahab Department of Biology, College of Science, University of Baghdad, Baghdad, Iraq. https://orcid.org/0000-0002-0226-5729

DOI:

https://doi.org/10.30526/39.2.4278

Keywords:

Gastric histology, Sciurus anomalus, Urva auropunctata, parietal cells, chief cells, feeding Habits

Abstract

The present study aims to elucidate the histological organization of the glandular stomach in two mammalian species exhibiting different feeding habits: (i) an herbivorous rodent, i.e., the Persian squirrel (Sciurus anomalus); and (ii) a carnivorous mammal, i.e., the small Asian mongoose (Urva auropunctata). Histological sections (n = 5) were taken from both groups and stained with hematoxylin and eosin (H&E), Alcian blue-PAS stain, and Masson’s trichrome, then microscopic examination was carried out distinct structural adaptations in the gastric mucosa, submucosa, muscularis, and serosa layers could be observed. The squirrel stomach exhibited a moderately thick mucosal layer with abundant mucus-secreting cells, and chief cells, reflecting its herbivorous diet.In contrast, the stomach of a mongoose had a thickened mucosal layer rich in oxyphilic (parietal) cells and a triple-layered muscularis, adaptations corresponding to its carnivorous diet. Mongoose gastric glands were more organized into tubular shapes, and a unique double-layered muscularis mucosae was also observed. This provides insight into processes underlying metabolic adaptations to dietary specialization in mammals, and evolutionary associations among gut size and efficiency according to feeding ecology

Author Biographies

Rafal Ayad Mahdi, Department of biology, College of Science, University of Baghdad, Iraq

-
Sura Abdul Munaff Abdul Wahab, Department of Biology, College of Science, University of Baghdad, Baghdad, Iraq.

-

References

1. Ghadirian Baharanchi O, Hemami MR, Yousefpour R. Spatial conservation prioritization of Persian squirrel based on habitat suitability and climate-induced forest mortality risk. Forests. 2024;15(2):290. https://doi.org/10.3390/f15020290.

2. Louppe V, Lalis A, Abdelkrim J, Baron J, Bed’Hom B, Becker AA, Russell JC, Zini V, Vidal E, Courchamp F. Dispersal history of a globally introduced carnivore, the small Indian mongoose Urva auropunctata, with an emphasis on the Caribbean region. Biol Invasions. 2021;23(8):2573–2590. https://doi.org/10.1007/s10530-021-02523-6.

3. Langer P, Clauss M. Morphological adaptation of the eutherian gastrointestinal tract to diet. Vertebr Zool. 2018;68:237–252. https://doi.org/10.5167/uzh-157906.

4. Duque-Correa MJ, Curtis EA, Elgar MA, Cooper N, Geiser F, Lovegrove BG, Withers PC, White CR. Mammalian intestinal allometry, phylogeny, trophic level and climate. Proc Biol Sci. 2021;288(1944):20202888. https://doi.org/10.1098/rspb.2020.2888.

5. Massoud E, El‐Kott A, Morsy K, Massoud D. Histology of the stomach in the Caucasian squirrel. Microsc Res Tech. 2022;85(6):2305–2312. https://doi.org/10.1002/jemt.24087.

6. Barbero S, Casanovas-Vilar I, Angelone C, Blanco F, Moyà-Solà S, Marín-Moratalla N. Linking diet, body mass, and stomach morphology in rodents. Can J Zool. 2021;99(10):885–901. https://doi.org/10.1139/cjz-2021-0042.

7. Abi-Said MR, Abi-Said D, Moussa R, Rifai L, Tohmé H, Tohmé G. Ecology of the Persian squirrel. Vertebr Zool. 2014;64:127–135. https://doi.org/10.3897/vz.64.e31471.

8. Koprowski JL, Gavish L, Doumas SL. Sciurus anomalus (Rodentia: Sciuridae). Mamm Species. 2016;48(934):48–58. https://doi.org/10.1093/mspecies/sew004.

9. Hays WST. Small Indian mongoose. In: Simberloff D, Rejmánek M, editors. Encyclopedia of Biological Invasions. Berkeley (CA): Univ. of California Press; 2019. https://doi.org/10.1525/9780520948433.

10. Berentsen A, Johnson S, VerCauteren KC. Ecology of the small Indian mongoose (Herpestes auropunctatus). In: Pitt WC, Beasley JC, Witmer GW, editors. Biology and Management of Invasive Species. Boca Raton (FL): CRC Press; 2018. p. 251–268. https://doi.org/10.1201/9781315157078-13

11. Tootian Z, Jalali A, Hassanpour H, Pourkabir M, Parto P, Zarei M. Histological study of the small intestine of the Persian squirrel. Anat Sci Int. 2013;88(1):38–45. https://doi.org/10.1007/s12565-012-0159-5.

12. Mahmood HB, Kadhim KK. Histomorphology and histochemical study of esophagus and stomach in grey mongoose (Herpestes edwardsii) in Iraq. Indian J Nat Sci. 2019;9(52):16458–16475.

13. AL-Nakeeb GD, Abid SA, Fadhil LA, Abdul Hussein RA. Comparative histological study of the stomach in two species of Iraqi vertebrates (Magpie Pica pica L. and Small Asian Mongoose Herpestes javanicus E.). Baghdad Sci J. 2019;16(2):281-286. https://doi.org/10.21123/bsj.2019.16.2.0281.

14. Di Natale MR, McCann CJ, Montgomery A, Pereira J, Young RL, Costa M, Bravo DM, Brookes SJH. Functional and anatomical gastric regions and their relations to motility control. Neurogastroenterol Motil. 2023;35(9):e14560. https://doi.org/10.1111/nmo.14560.

15. Mnati IM, Ahmed AM, Mutlak BH. The histological study of the ileum in the Caucasian squirrel Sciurus anomalus. Ibn Al-Haitham J Pure Appl Sci. 2022;35(4):13–20. https://doi.org/10.30526/35.4.2859.

16. Wolfe D. Tissue processing. In: Suvarna SK, Layton C, Bancroft JD, editors. Bancroft’s Theory and Practice of Histological Techniques. 8th ed. London: Elsevier; 2018. p. 73-83.

17. Ezennubia KP, Ofoegbu CJ, Adeniran TR, Jaiyeola TO. Effect of ground coffee beans extract on the histological structures of alloxan induced diabetes female albino rats. BIOMED Natural and Applied Sciences. 2025;5(3):01-16. https://doi.org/10.53858/bnas05030116.

18. SPSS. Statistical packages of social sciences – SPSS/IBM Statistics 26 step by step. 16th ed. 2019. https://doi.org/10.4324/9780429056765.

19. Sapundzhiev E, Chervenkov M, Hristakiev L. Histological gastric structure of badger (Meles meles). Acta Morphol Anthropol. 2019;26(3–4):68–72.

20. Hinton HE, Dunn AS. Mongooses: their natural history and behaviour. Berkeley (CA): Univ. of California Press; 2023. https://doi.org/10.1525/9780520329904.

21. Hyder I, Reddy PRK, Mukherjee J. Physiology of digestion. In: Textbook of veterinary physiology. Singapore: Springer Nature Singapore; 2023. p. 315-351.

22. Tamura N, Ito M, Hayashi F. Different responses of endemic and alien tree squirrels to tree seed chemicals. Mamm Study. 2021;46(3):237–50. https://doi.org/10.3106/ms2020-0108.

23. Menéndez I, Swiderski DL, Gómez Cano AR, Álvarez-Sierra MÁ, Hernández Fernández M, Zelditch ML. Dietary adaptations and tooth morphology in squirrels. Palaeogeogr Palaeoclimatol Palaeoecol. 2023;629:111788. https://doi.org/10.1016/j.palaeo.2023.111788.

24. Mahmood HB, Obead WF, Al-Aameli MH. A review of morphological and histological features of the stomach in carnivores. Karbala J Pharm Sci. 2023;21(1):99-107.

25. AL-Taai SAH, Nsaif RH, Almayahi MS. Histomorphological study of esophagus in squirrel (Sciurus anomalus). Biochem Cell Arch. 2021;21:1391–1394. https://doi.org/10.1111/ahe.12465.

26. Stockman J, Petritz OA. Nutrition for Small Mammalian Companion Herbivores and Carnivores. Appl Vet Clin Nutr. 2023;590–609 https://doi.org/10.1002/9781119375241.ch23.

27. Hussein AA, Abed WB. Morphological comparative study of the stomach in the Felis catus (domestic cat) and Sciurus carolinensis (eastern gray squirrel). Biochem Cell Arch. 2019;19(2)..

28. Menéndez I, Swiderski DL, Gómez Cano AR, Hernández Fernández M, Álvarez-Sierra MÁ, Zelditch ML. Diet versatility and functional trade-offs shape tooth morphology in squirrels. Evolution. 2023;77(1):83–96. https://doi.org/10.1093/evolut/qpac051.

29. Clauss M, Fritz J, Hummel J. Teeth and the gastrointestinal tract in mammals: when 1+1=3. Philos Trans R Soc Lond B Biol Sci. 2023;378(1891):20220544. https://doi.org/10.1098/rstb.2022.0544.

30. Furness JB. Comparative and evolutionary aspects of the digestive system and its enteric nervous system control. In: The Enteric Nervous System II. Cham: Springer; 2023. p.165–177. https://doi.org/10.1007/978-3-031-05843-1_16.