Nifty John , Mohamed Hatha Abdulla

Department of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Lakeside Campus, Cochin University of Science and Technology, Cochin-682 016, Kerala, India
Author    Correspondence author
International Journal of Aquaculture, 2013, Vol. 3, No. 17   doi: 10.5376/ija.2013.03.0017
Received: 30 May, 2013    Accepted: 03 Jun., 2013    Published: 20 Jun., 2013

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

John, 2013, Distribution, Extracellular Virulence Factors and Drug Resistance of Motile Aeromonads in Fresh Water Ornamental Fishes and Associated Carriage Water, International Journal of Aquaculture, Vol.3, No.17 92-100 (doi: 10.5376/ija.2013. 03.0017)

During last decades there has been a continuous growth of aquaculture industries all over the world and taking into consideration the spurt in freshwater ornamental fish aquaculture and trade in Kerala, the present study was aimed to assess the prevalence of various motile Aeromonas spp. in fresh water ornamental fishes and associated carriage water. The extracellular virulence factors and the antibiogram of the isolates were also elucidated. Various species of motile aeromonads such as Aeromonas caviae, A. hydrophila, A. jandaei, A. schubertii, A. sobria, A. trota and A. veronii were detected. Aeromonas sobria predominated both fish and water samples. Extracellular enzymes and toxins produced by motile aeromonds are important elements of bacterial virulence. The production of extracellular virulence factors-proteases, lipase, DNase and haemolysin by the isolates were studied. All the isolates from both fish and water samples produced gelatinase and nuclease but the ability to produce lipase, caseinase and haemolysins was found to vary among isolates from different sources. Among the 15 antibiotics to which the isolates were tested, all the isolates were found to be sensitive to chloramphenicol, ciprofloxacin and gentamicin and resistant to amoxycillin. Local aquarists maintain the fish in crowded stressful conditions, which could trigger infections by the obligate/ opportunistic pathogenic members among motile aeromonads.

Ornamental fish; Motile aeromonads; Antibiotic resistance; Diseases