Al-Qadisiyah Journal of Veterinary Medicine Sciences

Histopathological Assessment of Goldfish (Carassius auratus) Gills Under Aquatic Pollution Conditions

Document Type : Research Paper

Author

Asawer Abd Al Jabbar

Department of Pathological analysis, College of Science, University of Wasit, Al-Kut City, Iraq

https://doi.org/10.29079/qjvms.2026.170841.1183
Abstract
Gills consist of specialized structures including primary and secondary lamellae, chloride cells, epithelial cells, mucous cells, and venous sinuses, which are crucial for breathing and osmotic pressure management. The findings underscore substantial histological alterations caused by pollution exposure. Carassius auratus collected from ornamental fish shops in five different locations of Wasit Governorate, at a rate of four goldfish from each site. In addition, five water samples were collected from the same ponds from which the fish were obtained, the necessary chemical and physical analyses were conducted on them to determine the levels of pollutants in those ponds. The physicochemical analyses of the water revealed a clear, significant difference regarding the level of contamination in that water. On the other hand, histological results of the gills after they were stained with routine dye H&E observed the primary and secondary lamellae in addition to, appearance of oedema and epithelial lifting in the tissue. Meanwhile, the histochemical results of the samples revealed a strong positive in  mucous cell, and hyper secretion inter lamellae positive mucous cell hyperplasia with PAS stain. In addition, Mason's trichrome stain was used in present work to visualize collagen fibers; here, we note moderate fibrosis with lamellae fusion, hyperplasia and vascular congestion.

Keywords

Histopathological
Goldfish
Gills
Water pollution
Carassius auratus
Al-Qadisiyah Journal of Veterinary Medicine Sciences
Volume 25, Issue 1
May 2026
Pages 194-202