Apparent digestibility coefficients of brewer's by-products used in feeds for rainbow trout (Oncorhynchus mykiss) and gilthead seabream (Sparus aurata)

Abstract A trial was conducted to test the effect of partial replacement fishmeal by two brewery industry byproducts, yeast and spent grain, included in isoproteic (41% CP) isolipidic (22% CL) diets for gilthead sea bream (Sparus aurata) rainbow trout (Oncorhyncus mykiss), having mind availability these byproducts. first step before an ingredient is a commercial feed evaluate nutritional quality raw materials measuring their digestibility. Thus, apparent digestibility coefficients ingredients were determined after 30 days feeding faecal collection. Apparent products case varied between 75 88% whereas seabream 71 88%. According results obtained, inclusion 20–30% brewers' grain carnivorous fish either from fresh (rainbow trout) or marine (gilthead seabream) gave similar with meal as main protein source show good protein, lipid amino acid Taking into account that by-products are produced large quantities Europe, they can be potential reduce use plant proteins fish/animal byproducts (trimmings) increase sustainability both sectors, aquaculture.