Nutrigenomic studies elucidating the metabolic changes expected to take place in salmon fed diets based on sustainable protein sources

Fish fed plant proteins or diets very low in marine proteins generally show reduced growth compared to fish fed fishmeal based diets. In an experiment conducted last year we succeeded in preparing a diet composed of plant protein low in the essential amin o acids lysine, arginine, threonine and tryptophane that supported growth equally well as did a control fishmeal based diet. This diet was supplemented the mentioned amino acids from a synthetic source, and additionally added nitrogen rich factors necessa ry for optimal growth (Espe et al., unpublished results). This diet will be used as a tool in the present project to study the true requirement of the essential amino acids threonine, tryptophan, lysine and methionine. The studies will be performed with Atlantic salmon post smolts. Simultaneously the metabolic effect of feeding salmon plant proteins will be elucidated. The aim is to be able in future to compose fish feeds consisting of plant proteins that support protein growth and metabolism equally we ll as do fishmeal based diets. We will use nutrigenomic as a tool to reach ours goals. The salmon genome is about to be mapped and libraries are available for thousands of genes.