Protein‐rich product recovered from brewer's spent grain can partially replace fishmeal in diets of Pacific white shrimp,Litopenaeus vannamei

A protein‐rich product (PP) with 46% protein and less than 1% fibre was recovered from brewery's spent grain. This study aimed to investigate the effects of replacing dietary fishmeal with PP on the growth, feed utilization efficiency and nutritional composition of Pacific white shrimp, Litopenaeus vannamei. The control diet (PP0, containing 35% fishmeal) was compared with four isonitrogenous (44% crude protein), isolipidic (10% crude fat) and isocaloric (20 kJ/g) test diets, PP10, PP30, PP50 and PP70, which were formulated using PP protein to replace 10%, 30%, 50% and 70% of fishmeal protein. Sextuplicate groups of shrimp (averaging 1.10 g) were fed each of the five diets for 8 weeks. The results showed that up to 50% of fishmeal replaced with PP did not negatively affect the shrimp survival, growth performance, feed utilization efficiency, or the protein content and amino acid profile of shrimp. However, replacing 70% of fishmeal protein with PP protein negatively affected the percent weight gain and specific growth rate of shrimp, although the shrimp survival rate and feed conversion ratio were not affected.