Abstract

The present study aimed to develop and compare the efficacies of Formalin killed bacterin (FKB) administration by various routes against V. alginolyticus and L. anguillarum in sea bass, also, evaluation the efficacy of different administration routes through RLP and antibody titers; and determination the cross protective mechanisms induced by each vaccination protocol.
A total of apparently healthy 540 sea bass Dicentrarchus labrax juveniles weighing 25 ± 2 g was transported to the wet lab at Borg El Arab, Alexandria province, Egypt and acclimated for a period of 10 day in 4 aquariums and supplemented with seawater. A total 270 healthy fingerlings of sea bass weighing 25 ± 2 g / fish were used in this experiment for evaluated Vaccination against both V. alginolyticus and L. anguillarium as well as challenge with V. alginolyticus. V. alginolyticus monovalent vaccine was administered through dipping and i/P injection.
It could be concluded that; Vibriosis is a highly pathogenic disease not only to Seabass but also to other marine fish and human thus the prevention measures and strict veterinary hygienic regulations using vaccination through I/P injection should be implemented to control such infections and improve mariculture production in Egypt that is to minimize the antimicrobial use in fish farms which construct a high risk to human health, aquaculture and all environment.

Key words: Immune status - Sea bass Dicentrarchus labrax - Killed vaccine – Vibriosis