Short communicationAntibiotic resistance of Aeromonas hydrophila isolated from marketed fish and prawn of South India
Introduction
Wide use of antibiotics to treat bacterial infections and incorporation of subtherapeutic dose of antibiotics into feeds for cultured organism resulted in a global increase in antibiotic resistance among pathogenic bacteria. The problem is more serious in developing countries, where antibiotics are used widely. In India, antibiotics are extensively applied in animal husbandry and aquaculture.
The use of antibiotics is the most important factor in amplifying the level of resistance in a given reservoir (Wegener and Frimodt-Moller, 2000). Multiple antibiotic resistance (MAR) among Aeromonas hydrophila strains has been reported from many parts of the world Pettibone et al., 1996, Son et al., 1997, Ko et al., 1998, Rajeswari Shome and Shome, 1999. Under these circumstances, it will be worthwhile to find out the prevalence of antibiotic resistance of the Aeromonas strains that may be considered as an emerging pathogen and to identify the high-risk source.
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Materials and methods
The fish and prawn samples were collected from a major fish market of Coimbatore, Tamil Nadu, South India. The samples were collected in sterile polyethylene bags and brought to the laboratory in an ice chest. The samples were processed within 2 h of collection. Body surface, gill and intestinal content of fish were aseptically swabbed using sterile cotton buds, inoculated into alkaline peptone water (peptone—10.0 g; sodium chloride—10.0 g; distilled water—1000 ml; pH—8.4, Shread et al., 1981)
Results and discussion
The percentage of A. hydrophila strains showing resistance against each antibiotic is given in Table 1. All the strains were resistant to methicillin, which was similar to the findings of Motyl et al. (1985) who reported that all A. hydrophila strains of human origin were resistant to methicillin. In contrast, Pettibone et al. (1996) observed that only 54% of the strains was resistant to this antibiotic. However, Kampfer et al. (1999) reported that no significant differences could be observed
Acknowledgments
The authors are thankful to the Head, Department of Environmental Sciences, Bharathiar University, Coimbatore for providing necessary laboratory facilities and also to Indian Council of Agricultural Research (4 (49)/97-ASR-1 dt 22.09.2001) for the financial support.
References (23)
Numerical taxonomy of Aeromonadaceae and Vibrionaceae associated with reared fish and surrounding fresh and brackish water
Syst. Appl. Microbiol.
(1995)- et al.
Behaviour in conventional purification process of coliform bacteria with transferable and non-transferable drug resistance
Water Res.
(1976) - et al.
In vitro susceptibilities of Aeromonas genomic species to 69 antimicrobial agents
Syst. Appl. Microbiol.
(1999) - et al.
Plasmids and antibiotic resistance in Aeromonas hydrophila
J. Fish Biol.
(1992) - et al.
Antibiotic susceptibility testing by a standard single disk method
Am. J. Clin. Pathol.
(1966) - et al.
Plasmids and resistance to antimicrobial agents in Aeromonas hydrophila clinical isolates
Antimicrob. Agents Chemother.
(1987) - et al.
Biochemical characterization, enteropathogenicity and antimicrobial resistance plasmids of clinical and environmental Aeromonas isolates
J. Med. Microbiol.
(1996) - Conn, H.J., 1957. Staining methods. In: Society of American Bacteriologists Committee on Bacteriological Technic (Ed.),...
- et al.
Survival in maturation ponds of coliform bacteria with transferable drug resistance
Water Res.
(1973) - et al.
Medium for the presumptive identification of A. hydrophila and enterobacteriaceae
Appl. Environ. Microbiol.
(1979)