Comparative observation of the organ development and health of the tropical oyster Crassostrea belcheri (Sowerby, 1871) in hatchery and wild farming sites
Issued Date
2026-09-01
Resource Type
eISSN
26299968
Scopus ID
2-s2.0-105029216174
Journal Title
Veterinary Integrative Sciences
Volume
24
Issue
3
Rights Holder(s)
SCOPUS
Bibliographic Citation
Veterinary Integrative Sciences Vol.24 No.3 (2026)
Suggested Citation
Chooseangjaew S., Tanyaros S., Kongthong K., Thaochan N., Dusitsittipon S., Sornying P., Iida A., Boonyoung P., Senarat S. Comparative observation of the organ development and health of the tropical oyster Crassostrea belcheri (Sowerby, 1871) in hatchery and wild farming sites. Veterinary Integrative Sciences Vol.24 No.3 (2026). doi:10.12982/VIS.2026.066 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/114964
Title
Comparative observation of the organ development and health of the tropical oyster Crassostrea belcheri (Sowerby, 1871) in hatchery and wild farming sites
Corresponding Author(s)
Other Contributor(s)
Abstract
The tropical oyster, Crassostrea belcheri, is an important, high-value seafood in aquaculture in Thailand. Understanding the development and physiological responses of C. belcheri in different rearing conditions is essential for sustainable production. This study compared the histological structures, mucus-secreting cell (MSC) distributions, and gonadal development of C. belcheri sampled from a hatchery (HAT) and three open-sea farming sites. The sampled oysters were classified into five categories based on shell height: 1.0–2.5 cm, 2.6–4.1 cm, 4.2– 5.7 cm, 5.8–7.3 cm, and 7.4–8.8 cm. Size-and site-dependent differences in organ morphology were observed. In the largest HAT oysters, the average gill lamella length was 128.8 ± 7.3 µm; average mantle epithelium thickness 14.1 ± 1.0 µm and average digestive tubule diameter 86.5 ± 2.2 µm. All three morphometrics differed significantly across the four sites (p < 0.05). Four MSC morphotypes were observed. Gonadal development followed a protandric pattern, with male gametogenesis observed in oysters smaller than 5.8 cm and female oogenesis being dominant in larger individuals (> 5.8 cm). Oocyte maturation across sites was consistent rather than site dependent. Histopathological evaluation using the Health Assessment Index (HAI) revealed sublethal tissue alterations, including epithelial atrophy, digestive tubule regression and gill lamellar fusion, with a mean HAI score of 3.7 ± 1.2 for wild-farmed oysters compared with 1.8 ± 0.9 for HAT samples. These findings underscore strong associations between oyster size, environmental conditions and organ development, and the potential of MSC density and histopathological lesions as reliable biomarkers for aquaculture monitoring and health management in C. belcheri.