Open Access
Research (Published online: 23-09-2023)
24. Isolation, genetic characterization, and virulence profiling of different Aeromonas species recovered from moribund hybrid catfish (Clarias spp.)
Dini Siswani Mulia, Rarastoeti Pratiwi, Widya Asmara, Mohamad Azzam-Sayuti, Ina Salwany Md. Yasin, and Alim Isnansetyo
Veterinary World, 16(9): 1974-1984

Dini Siswani Mulia: Department of Biology Education, Faculty of Teacher Training and Education, Universitas Muhammadiyah Purwokerto, Jl. K.H. Ahmad Dahlan, Purwokerto 53182, Indonesia.
Rarastoeti Pratiwi: Department of Biology, Faculty of Biology, Universitas Gadjah Mada, Jl. Teknika Selatan, Senolowo, Yogyakarta 55281, Indonesia.
Widya Asmara: Department of Microbiology, Faculty of Veterinary Medicine, Universitas Gadjah Mada, Jl. Fauna, Caturtunggal, Yogyakarta 55281, Indonesia.
Mohamad Azzam-Sayuti: Laboratory of Aquatic Animal Health and Therapeutics, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Ina Salwany Md. Yasin: Laboratory of Aquatic Animal Health and Therapeutics, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Alim Isnansetyo: Department of Fisheries, Faculty of Agriculture, Universitas Gadjah Mada, Jl. Flora, Bulaksumur, Yogyakarta 55281, Indonesia.

doi: 10.14202/vetworld.2023.1974-1984

Article history: Received: 11-05-2023, Accepted: 31-08-2023, Published online: 23-09-2023

Corresponding author: Alim Isnansetyo

E-mail: isnansetyo@ugm.ac.id

Citation: Mulia DS, Pratiwi R, Asmara W, Azzam-Sayuti M, Yasin ISM, and Isnansetyo A (2023) Isolation, genetic characterization, and virulence profiling of different Aeromonas species recovered from moribund hybrid catfish (Clarias spp.), Veterinary World, 16(9): 1974-1984.
Abstract

Background and Aim: The high diversity of Aeromonas spp. results in various pathogenicity levels. This group of bacteria causes a serious disease named motile Aeromonas septicemia (MAS) in catfish (Clarias spp.). This study aimed to characterize the species and virulence gene diversity of Aeromonas spp. isolated from diseased catfish.

Materials and Methods: Nine Aeromonas spp. were isolated from infected catfish cultivated in Java, Indonesia, and they were identified at the phenotypic and molecular levels (16S rDNA). The virulence genes assessed included aer/haem, alt, ast, flaA, lafA, and fstA.

Results: Phylogenetic analysis identified nine isolates of Aeromonas spp.: Aeromonas hydrophila (11.11%), Aeromonas caviae (11.11%), Aeromonas veronii bv. veronii (44.44%), and Aeromonas dhakensis (33.33%). Virulence genes, such as aer/haem, alt, ast, flaA, lafA, and fstA, were detected in all isolates at frequencies of approximately 100%, 66.67%, 88.89%, 100%, 55.56%, and 66.67%, respectively. This study is the first report on A. dhakensis recovered from an Indonesian catfish culture. Furthermore, our study revealed the presence of A. veronii bv veronii, a biovar that has not been reported before in Indonesia.

Conclusion: This finding confirms that MAS was caused by multiple species of Aeromonas, notably A. dhakensis and A. veronii bv veronii, within Indonesian fish culture. The presence of these Aeromonas species with multiple virulence genes poses a significant threat to the freshwater aquaculture industry.

Keywords: 16S rDNA, aeromoniasis, motile Aeromonas septicemia, pathogenicity, phenotype, phylogenetic.