Project description:The processing of seafood for human or animal consumption creates vast amounts of by-product, which is often considered waste. Although some of these by-products are used as fishmeal, bone-meal or fertilizer, as a whole, it remains under utilized. Significant amounts of proteins, lipid fractions, vitamins, and other bioactive molecules are present in these by-products, all with potential beneficial properties that could be used as alternatives to fishmeal or as supplements for aquaculture species. In an attempt to investigate their potential benefit in Atlantic salmon fish nutrition, nine experimental diets were formulated using by-products originating from various seafood processing plants. A control basal diet (no by-product added) was also formulated. Juvenile Atlantic salmons were fed one of the nine experimental diets (30% marine by-product, 70% basal diet) or the basal diet and hepatic gene expression profiling was done on fish fed each diet after 14 and 56 days. Analysis of hepatic gene expression revealed a significant amount of differentially expressed genes for each diet with roles in various pathways and biological processes. By comparing differences in hepatic gene expression levels with the nutritional composition of the various feeds, we were able to identify a number of nutritional elements that affect specific gene families. This information will be very useful for the formulation of novel fish feeds, which may be designed with specific aims, such as rapid growth, increased immunity or better general health This specific study is aimed at evaluating the hepatic transcriptional responses in juvenile Atlantic salmon fed with fish feed formulation supplemented with one of nine marine by-products.
