Caspian Journal of Veterinary Sciences

Caspian Journal of Veterinary Sciences

Report of Saprolegnia Salmonis infection in ornamental fish

Document Type : Scientific report

Authors
Iradj Ashrafi Tamai 1
Sepideh Asadi 1
Shirin Mohammadipour 2
Kiana Nazarpouri 3
1 Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
2 Department of Pathobiology, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran
3 Doctor of Veterinary Medicine Student, Science and Research Branch, Islamic Azad University, Tehran, Iran
10.22034/cjvs.2024.210716
Abstract
Saprolegniosis poses a significant challenge in the aquaculture industry, leading to substantial losses, including an estimated one egg loss for every thirty eggs in cold-water fish hatcheries (Masigol et al., 2021; Chanu et al., 2022). The Saprolegnia genus, classified under the Saprolegniaceae family, comprises water molds that thrive in freshwater environments. They are recognized as a critical fungal group affecting both farmed and wild fish.

This fungus is naturally found in fresh water and moist soil and is responsible for Saprolegniosis. Recently, several ornamental koi fish exhibiting symptoms such as white patches, weakness, lethargy, skin lesions, fin deterioration, and swimming incoordination were referred to the microbiology department at the Faculty of Veterinary Medicine, Tehran University. Initially, the symptoms raised suspicions of Cort syndrome; however, further testing confirmed Saprolegniosis.

Skin samples from the affected fish were collected and cultured on Sabouraud dextrose agar (SDA) at 20°C. Phenotypic methods were used to determine the genus of the fungus, followed by genotypic methods, specifically PCR, for species identification. The PCR product was sequenced by Sina Clone Company and deposited in a gene bank, ultimately confirming the presence of Saprolegnia salmonis.

Given the disease's direct correlation with the fish's living conditions, owners were advised to improve water quality, ensure appropriate living conditions, and manage dietary needs. Additionally, enhancing public awareness of Saprolegniosis and improving hygiene standards in endemic areas is recommended to mitigate its impact on the aquaculture sector.
Keywords
Fish
PCR
Saprolegnia
Saprolegniosis
Subjects
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Caspian Journal of Veterinary Sciences
Volume 1, Issue 2
December 2024
Pages 169-174

  • Receive Date 26 October 2024
  • Revise Date 02 November 2024
  • Accept Date 02 November 2024