Histological study of seventeen organs from dugong (Dugong dugon)

Patcharaporn Kaewmong; Pathompong Jongjit; Araya Boonkasemsanti; Kongkiat Kittiwattanawong; Piyamat Kongtueng; Pitchaya Matchimakul; Wasan Tangphokhanon; Prapawadee Pirintr; Jaruwan Khonmee; Songphon Buddhasiri; Promporn Piboon; Sonthaya Umsumarng; Raktham Mektrirat; Korakot Nganvongpanit; Wanpitak Pongkan

doi:10.7717/peerj.15859

Histological study of seventeen organs from dugong (Dugong dugon)

PeerJ. 2023 Aug 29:11:e15859. doi: 10.7717/peerj.15859. eCollection 2023.

Authors

Patcharaporn Kaewmong¹, Pathompong Jongjit¹, Araya Boonkasemsanti¹, Kongkiat Kittiwattanawong¹, Piyamat Kongtueng^{2

3}, Pitchaya Matchimakul⁴, Wasan Tangphokhanon⁴, Prapawadee Pirintr⁴, Jaruwan Khonmee^{3

4}, Songphon Buddhasiri^{3

4}, Promporn Piboon^{3

4}, Sonthaya Umsumarng^{3

4}, Raktham Mektrirat⁴, Korakot Nganvongpanit^{3

4}, Wanpitak Pongkan^{3

4}

Affiliations

¹ Phuket Marine Biological Center, Phuket, Thailand.
² Central Laboratory, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.
³ Research Center for Veterinary Biosciences and Veterinary Public Health, Chiang Mai University, Chiang Mai, Thailand.
⁴ Department of Veterinary Biosciences and Veterinary Public Health, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand.

Abstract

Background: Dugongs are marine mammals with a crescent-shaped tail fluke and a concave trailing margin that belong to the family Dugongidae., They are distributed widely in the warm coastal waters of the Indo-Pacific region. Importantly, the population of dugongs has decreased over the past decades as they have been classified as rare marine mammals. Previous studies have investigated the habitat and genetic diversity of dugongs. However, a comprehensive histological investigation of their tissue has not yet been conducted. This study provides unique insight into the organs of dugongs and compares them with other mammal species.

Methods: Tissue sections were stained with Harris's hematoxylin and eosin Y. The histological structure of 17 organ tissues obtained from eight systems was included in this study. Tissue sections were obtained from the urinary system (kidney), muscular system (striated skeletal muscle and smooth muscle), cardiovascular system (cardiac muscle (ventricle), coronary artery, and coronary vein), respiratory system (trachea and lung), gastrointestinal system (esophagus, stomach, small intestine, liver, and pancreas), reproductive system (testis), lymphatic system (spleen and thymus), and endocrine system (pancreas).

Results: While most structures were similar to those of other mammal species, there were some differences in the tissue sections of dugongs when compared with other mammalian species and manatees. These include the kidneys of dugongs, which were non-lobular and had a smooth, elongated exterior resulting in a long medullary crest, whereas the dugong pyloric epithelium did not have overlying stratified squamous cells and was noticably different from the Florida manatee.

Discussion: Histological information obtained from various organs of the dugong can serve as an essential foundation of basal data for future microanatomical studies. This information can also be used as high-value data in the diagnosis and pathogenesis of sick dugongs or those with an unknown cause of death.

Keywords: Dugong; Histology; Microanatomy; Organ; Tissue.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Caniformia*
Cetacea
Dugong*
Kidney
Male
Pancreas
Research Design
Sirenia

Grants and funding

This work was supported by Chiang Mai University through the Research Administration Office, which provided a budget to Research Center for Veterinary Biosciences and Veterinary Public Health, Chiang Mai University, Chiang Mai 50200, Thailand. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.