Reducing tank effects
Tank effects represent a recurring problem in fish challenge trials where multiple trial regimes are on test and where the trial groups must be held in separate tanks, such as feeding trials.
"Tank effects" may be defined as unintended variance between replicate tanks and will inevitably occur - even when all trial settings are highly standardized - as random noise. Typical measures to control for and counteract tank effects include increasing the number of replicate tanks in each trial regime and/ or increasing the number of fish in each tank.
Increasing fish expenditure in this way to counteract random noise is not desirable from an ethical and scientific point of view. VESO Vikan has strong and continuous focus on reducing fish expenditure in trials performed in our facilities albeit without compromising our ability to identify true underlying differences between test groups.
As a new step on this road we have developed a system where water in challenge tanks is shared between replicate tanks and across trial regimes during the course of the challenge. We hypothesize that sharing random events with all tanks will reduce variance and subsequently fish numbers needed in challenge trials.
For further information, please contact Christian Wallace.