The 3 R’s and behavioural studies in aquaculture: Trade off between possible animal suffering and relevance
Jon-Erik Juell, Institute of Marine Research, 5984 Matredal
Animal group size in experimental studies is usually decided based on expected within group variation and experimental design. Both from an animal welfare and economical view we need to balance the number of animals subjected to possible suffering with the required statistical power. However, another crucial ethical aspect is whether the experiment will result in relevant data for the research topic in question. Behavioural studies related to aquaculture often aim at understanding the priorities of the animal – what they prefer and need – in order to establish production protocols that ensure acceptable standards of animal welfare (Dawkins 2003). We need to understand the underlying mechanisms controlling behaviour under realistic culture conditions. Compared to e.g. nutritional or vaccine studies, context is highly important for the behavioural responses of animals. In commercial aquaculture fish are raised in groups of 10-100 thousands of individuals. Data from behavioural studies carried out in experimental conditions with only a small number of fish may reveal interesting results of the behaviour of fish in such a setting, but may not be relevant to the context of commercial aquaculture. Social interactions in connection with aggression, establishment of dominance hierarchies and schooling are influenced by group size. Experimental studies with few individuals may actually increase the degree of suffering and at the same time produce irrelevant data. One could argue that the need to Refine may counteract the need to Reduce when it comes to aquaculture related behavioural studies. However, to Replace by using individual based modelling is a potential future path that should be explored.
Dawkins, M.S. 2003. Behaviour as a tool in the assessment of animal welfare. Zoology (106) 383-387.