Characterisation of Non-tuberculous Mycobacteria Isolated from Apparently Healthy and Diseased Fresh Water Ornamental Fish in Sri Lanka

• Published in: Asian fisheries science Vol. 30; no. 2; pp. 118 - 129
• Main Author: DISSANAYAKE, D.R. ANURUDDHIKA
• Format: Journal Article
• Language: English
• Published: 2017
• Subjects: Freshwater; Mycobacterium chelonae; Mycobacterium fortuitum; Mycobacterium kansasii; Mycobacterium marinum; Sri Lanka
• ISSN: 0116-6514; 2073-3720
• DOI: 10.33997/j.afs.2017.30.2.005

Eighty nine fish including guppies (n=55), Siamese fighting fish (n=12), Swordtails (n=10), Platies (n=6) and goldfish (n=6) showing emaciation, scoliosis and loss of pigmentation, and 30 apparently healthy guppies collected from pet shops and fish breeding farms in Sri Lanka were examined and sampled to culture and isolate non-tuberculous mycobacteria (NTM). A total of 35 mycobacteria (diseased=28, healthy=7) isolated from these fish were subjected to biochemical identification and Polymerase Chain Reaction - Restriction Fragment Length Polymorphism (PCRRFLP). Only 24 NTM isolated from diseased fish were identified at the species level, namely Mycobacterium fortuitum type I (n=7), M. fortuitum type II (n=3), Mycobacterium kansasii type IV (n=5), Mycobacterium marinum (n=8) and Mycobacterium chelonae (n=1). Five of the seven NTM species isolated from apparently healthy fish were identified as M. fortuitum type I (n=2), M. fortuitum type II (n=1), M. kansasii type IV (n=1) and M. marinum (n=1). Irrespective of the NTM species involved, guppies most often showed skeletal deformities while chronic ulcers were common in goldfish and fighting fish. Histopathologically, granulomatous inflammation was minimum in guppies. All four NTM species isolated in this study are potentially zoonotic and it is necessary to implement appropriate biosecurity measures to prevent spread of these organisms.