Schering-Plough points to the success of producers using the company’s Total Protection Strategy, giving AquaVac* ERM oral as a booster vaccination following immersion prime vaccination with AquaVac ERM.
Dr. Chris Gould, Global Technical Services Manager with Schering-Plough Aquaculture explains, "Farmers who follow immersion with a booster vaccination have confidence that portion size trout will reach the end of the production cycle protected from ERM infection." He continues, "We believe that a majority of farmers are already employing the Total Protection Strategy but for those who are not, we are ready to advise on an oral boost."
Schering-Plough confirms the fact that immersion vaccination offers protection for young trout, however, in common with most animals, the immunity provided to the rainbow trout requires periodic boosting to maintain this protection. If this is not undertaken the rainbow trout can become vulnerable to ERM infection.
Effects of an ERM outbreak are well documented and include increased mortality, poorer growth, higher feed conversion rates and the possibility of antibiotic treatment. The consequences at harvest include size variability and lower average weights. The economic impact of infection in trout towards the end of the production cycle can be heavy as the fish already carry a significant amount of investment in feed costs and overheads.
Farmers interested in protecting their investment and extending their ERM cover by giving an oral boost should contact their vet or their local Schering-Plough representative. The company has also produced a series of bulletins designed to assist in vaccination planning. These can be downloaded at www.spaquaculture.com