A study on the effect of using mangrove leaf extracts as a feed additive in the progress of bacterial infections in marine ornamental fish

Objective:To ascertain the feasibility of using sustainable natural resources in maintaining disease free fish in such establishments.Methods:causative bacteria were identified by morphology and biochemical techniques.The antibacterial activity and disease resistant capability of mangrove plant leaf extract were investigated against fish pathogens.Results:The infected marine ornamental fishes were collected from the hatchery condition and inhibition activity at the concentration of 220,200,175 and 150μg/mL against Pseudomonas fluorescens,Pseudomonas aeruginosa,Vibrio parahaemolyticus,and Vibrio anguillarum respectively.The experimental trial reveals feeding marine ornamental fish with feed incorporated with a methanol leaf extract of Avicennia marina,increases their survival and reduces their susceptibility to infections from the isolated bacteria.Based on the in vitro assay,methanol extract of Avicennia marina was exhibited good Conclusions:The mangrove leaves have potential to control the infections caused by Pseudomonas fluorescens,Pseudomonas aeruginosa,Vibrio parahaemolyticus and Vibrio anguillarum.