Investigating the potential of nutritional programming to improve the utilisation of sustainable feeds in aquaculture

Our hypothesis is that nutritional programming can improve and enhance the capability of Atlantic salmon to effectively andefficiently utilise sustainable feeds formulated with very low levels of marine ingredients. The nutritional programmingconcept involves exposing an animal to a dietary stimulus early in life that alters that individual metabolically andphysiologically such that it becomes adapted and better able to respond to a similar nutritional challenge later in life. Thisconcept was first studied and demonstrated in rodents and subsequently applied to both human and agricultural livestockanimals and, more recently, was demonstrated to be applicable in some fish species. Recently, we showed that an earlynutritional intervention in Atlantic salmon at first feeding using a diet formulated almost entirely with plant proteins and oils,with only a very low level of fishmeal and no fish oil, resulted in fish better adapted to utilise this feed later in life. Thus,when challenged with this diet 3 months later, the fish showed improved growth performance despite having similar feedintake, which was reflected in higher feed efficiency and increased nutrient retention. Specifically, the retentions of the keyomega-3 fatty acids, EPA and DHA, were greatly increased in fish subjected to the nutritional programming. The overallaim of the present project is to determine the optimal feeding regime to enable nutritional programming in salmon and toassess the long-term effects (18 months) of a short (~1 week) nutritional intervention at first feeding on Atlantic salmon.Growth, feed efficiency and nutritional quality will be assessed and the underlying molecular mechanisms of bothmetabolism and immune function will provide insights to the processes underpinning the response to initial diet, and toassess the potential for commercial application.