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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
In the present investigations, whole body extract of earthworm, Eisenia fetida was tested for antibacterial activity against fish bacterial pathogens. The bacteria were isolated from different tissues of infected common carp, Cyprinus carpio and identified by gram staining method. A total of eight pathogenic bacteria were isolated. Antimicrobial activity of the extract was studied under in vitro conditions by well diffusion assay. The extract of Eisenia fetida showed antibacterial activity against all the pathogenic bacteria and the maximum zone of inhibition was observed against A. hydrophila. Histological investigations had revealed that feeding the fish on a diet prepared by incorporating earthworm extract resulted in an increase in intestinal folds while injecting the fish with A. hydrophila resulted in degeneration and desquamatation of intestinal epithelium feeding on supplementary diet. When a healthy carp was injected with pathogenic bacterium and also fed on a diet prepared in earthworm extract, it resulted in a significant (P<0.05) increase in intestinal folds, intestinal microvilli, increase in concentration of melano-macrophage centre and also haemopoietic tissue in the kidneys. From these studies, it was concluded that the earthworm extract possesses very strong antibacterial properties which could be employed in treating bacterial infections in fishes, leading to the availability of antibiotic free fishes to the consumers.