Technical aspects of the administration of vaccines

The practise of vaccination as a standard part of fish husbandry has led during the last 20 years to the adoption of a number of basic vaccination regimes based on an understanding of the principles involved and how to maximize protection. The strategies adopted depend on the species of fish, its husbandry, the disease against which protection is sought and the optimum timing within the growth cycle so that the predicted duration of protection coincides with the timing of any expected disease challenge. These and other parameters influencing the performance of vaccines are discussed in the context of what is practical and cost-effective in each circumstance and the risks involved in handling and administering vaccine by the different available methods.