Plant oils as fish oil replacements in fish feeds

The increasing aquaculture of predatory carnivorous fish demands new sources of feed constituents , especially oils. Land grown oil plants lack the long chained polyunsaturated fatty acids. In connection with fish feed, especially the lack of n-3 ”marine fatty acids” is obvious. Therefore strategies with a finishing diet have been developed, where plant oil based feed during the on growing phase of the fish is replaced by fish oil diet during a few months before slaughter. This regime restores most of the beneficial lipid composition of fish in terms of human diet. Very little attention has been directed the fish well being and studies are still scarce. Other lipid compounds of plant oils in fish feeds have been so far mostly overlooked. Effects of minor lipid compounds such as phytoestrogens, phytosterols, phenolic compounds – very often bioactive substances- have to be investigated in near future in connection both to fish and human health