Plant-based diet in trout (O. mykiss): are there genotype-diet interactions for main production traits when fish are fed marine vs plant-based diets from the first meal ?

To face future decrease of marine resources, replacement of fishmeal and fish oil by plant products is nowadays worldwide priority for the aquaculture of carnivorous fish, especially salmonids. Genetic variability has been recently evidenced for growth ability on plant-based diet and pointed out potential genetic gains. In a context of fast feed evolution, this work compares heritabilities of growth parameters between rainbow trout fed with diet containing fish oil and fish meal and fish fed on diet devoid of marine products. Assessment of genotype diet interaction informs on potential family reranking between diets and potential consequences on current breeding programmes.