A study on the control of Aeromonas hydrophila infection in the cat fish by medicinal plants

Aeromonas hydrophila was obtained from various sources and identified on the basis of growth on selective media, phenotypic and biochemical characters. The isolates (Ah1-Ah9) were subjected to antibiotic susceptibility and resistance pattern tests. The isolates showing maximum resistance to most of the commercial antibiotic discs used were selected. The selected isolate (Ah7) was further subjected to check its susceptibility towards six medicinal plants (Mentha piperita,, Azadirachta indica, Andrographis paniculata, Phyllanthus niruri, Solanum nigrum, Ruta chalepensis) by using their solvent extracts through agar gel diffusion method. Two plant extracts ( Andrographis paniculata and Azadirachta indica ) were prominently showing maximum zone of inhibition (29mm and 27mm). This isolate (Ah7) was used to infect fresh water channel cat fishes. A significant association was found in control of Aeromonas hydrophila infection in the fish treated with medicinal herbs. While in untreated fish, it resulted in death with severe infected lesions.