Recovery of Multiple Drug Resistant Pseudomonads Associated with an Ulcerative Condition in an Airbreathing Murrel, Channa gachua Bl.

Abstract

Three species of Pseudomonas namely P. aeruginosa, P. putida and P. stuzeri were isolated from the sera, kidneys and livers of Channa gachua (Bloch) suffering from an ulcerative condition. Involvement of P. stuzeri in the ulcerative condition of fish is being reported for the first time. All the strains showed resistance to 11 out of the 15 drugs monitored in the present case, whereas P. stuzeri exhibited additional resistance to cotrimoxazole. Agarose gel electrophoresis against the control obtained by curing with sodium dodecyl sulfate revealed that all three species harboured plasmids which transformed susceptible Escherichia coli HB101 host. Transformation experiments demonstrated that except resistance to cotrimoxazole and ceftimaxazole all the others were plasmid-borne. Sensitivity to gentamycin, chloramphenicol and cefotaxime was also exhibited in each strain. Upon challenging the host using pure cultures of either strain, only symptoms of erythema and skin aberrations could be observed, while mixed culture of all the three induced moderate ulcers. On the basis of review of already published evidence, C. gachua may be considered as a host of exceptional endurance to ulcerative condition.