VACCINATION IN EUROPEAN SALMONID AQUACULTURE - A REVIEW OF PRACTICES AND PROSPECTS

Disease control by vaccination is widely used in European salmonid aqu a-culture against vibriosis (Vibrio anguillarum), cold-water vibrosis (Vibrio salmonicida), yersiniosis or enteric redmouth disease (Yersini a ruckeri) and furunculosis (Aeromonas salmonicida subsp. salmonicida) . The vaccines against the Vibrio spp. and Y. ruckeri have proven effe ctive especially when administered by injection. Furunculosis vaccines have been less successful and have relied on combination with potent adjuvants to achieve acceptable protection. Application of modern mole cular techniques to furunculosis research has delivered a crop of expe rimental vaccines that incorporate purified virulence factors and have shown increased protection during challenge. Gene technology has also been used to create a defined, non-reverting mutation in a strain of A. salmonicida, which has enhanced the feasibility of attenuated live vaccines. The development of experimental subunit vaccines against the viral infections and the continued advances in the field of immunosti mulants, adjuvants and antigen carriers provide considerable promise f or the future development of commercial vaccines for use in salmonid a quaculture.