Vaccination of Catla catla employing biofilm of Aeromonas hydrophila to enhance its immunity

Vaccination is considered as a sustainable strategy for disease prevention in aquaculture and further mucosal vaccines are the need of the hour which brings about local immune response and hence enhanced immunity. Oral vaccination is the preferred method but its efficacy depends on its appropriate delivery. In this study the effect of biofilm oral vaccine on gut immunity (mucosal immunity) was evaluated in comparison with serum antibody titre and protection upon challenge. In catla vaccinated with biofilm the serum antibody (OD) increased gradually, compared to the control reaching highest on 30dpv. A similar trend was observed in mucus antibody of catla vaccinated with biofilm compared with that of control. However, antibody concentration (OD) in mucus was almost 50per cent compared to that of serum. In unvaccinated control group survival was only 20 per cent compared to 86.66 per cent with biofilm vaccinated group.