MONTANIDE™ ISA 763 AVG adjuvant for efficient and safe fish vaccines

Objective: Most of bacterial diseases can be efficaciously controlled by a vaccination procedure composed of intraperitoneal injection of vaccine. Vaccines used in fish are generally inactivated pathogens associated with an adjuvant. In order to ensure a long lasting protection of fish, without performing several injections procedure, potent adjuvants are used in the vaccine formulation. The oil based vaccines are known to induce a long lasting immune response, but it can be linked to some side effects in the injection side. MONTANIDE™ ISA 763 is an oil adjuvant, designed to improve the safety of W/O type vaccines without reducing the vaccine Method & Materials: Montanide ISA 763 A VG contains an optimised mixture of pharmaceutical, injectable oils (non mineral oils) and a highly refinedemulsifier obtained from mannitol and purified oleic acid (anhydromannitol octadecanoate ether). This work illustrates both of the safety and efficacy properties of MONTANIDE™ ISA 763 A VG using rainbow trout as fish model and Lactococcus garviae aspathogen. Fish weighting 40g were provided with intraperitoneal injection and subjected to challenge 30 days after vaccination. Cumulative Mortality, Relative Per cent Survival (RPS), and the presence of undesired side-effects were recorded. Unvaccinated fish were used as control for challenge procedure. Results & Conclusion: The result demonstrates more than 72.8% of RPS at the end of the trial for the Montanide™ based formula. Sides effects were assessed using an internal scoring ladder from 0 (no reactions) to 4 (reactions preventing fish product sell). No local reactions were found in score 4, around 50% of animal presented less than score 3 reactions. This study demonstrates the ability to efficiently use the MONTANIDE™ ISA 763 A VG for fish vaccine formulation. It means that MONTANIDE™ ISA 763 A VG is an oil adjuvant, designed to improve the safety of W/O type vaccines without reducing the vaccine efficacy