LAUSR

Abstract An eight-week feeding trial was carried out to examine the effects of diets formulated with different combinations of novel feed ingredients as substitutes for fishmeal (FM). The research focused on evaluating their influence on fatty acid and amino acid profiles, immunological and plasma biochemical analysis, immune related gene expression and histological analysis of Pacific white shrimp, Penaeus vannamei. Five diets were developed for Penaeus vannamei, all of which were isonitrogenous (36%) and isolipidic (6%). Diet 1 (control): primary source of protein was fishmeal (FM); diet 2: replaced FM with a 1:1 ratio of poultry by-product meal (PBM) and single-cell protein (SCP); diet 3: replaced FM with a 1:1:1 ratio of insect meal (IM), rapeseed meal (RM), and SCP; diet 4 replaced FM with fish waste (FW), peanut meal (PM), and SCP in a 1:1:1 ratio; diet 5 replaced FM with PBM, SCP, IM, FW, PM, and RM in equal amounts (1:1:1:1:1:1). Nursery reared juvenile shrimps (1.05± 0.03 g) were stocked in triplicates in the experimental tanks at the rate of 35 shrimp per tank. The plasma biochemical responses and amino acid profile did not differ significantly (P>0.05) between the dietary groups. EPA was significantly higher in diets 1 and 5 which was not different from diet 4 and DHA was significantly higher in diet 1 which was not different from diet 5. Prophenoloxidase activity (proPO) was significantly higher (P<0.05) in diets 1 and 5, and respiratory burst activity was significantly (P<0.05) higher in diets 1 and 5 which was not different from diet 3. The immune gene expression (LYZ) was upregulated in diets 1 and 5. More B cells and few R cells were observed in diets 1 and 5 compared to other diets. Thus, the present study concluded that a mixture of PBM, SCP, IM, RM, PM and FW (1:1:1:1:1:1) serves as a good combination diet to totally replace FM in shrimp feed without compromising the fatty acid and amino acid profile and health of Pacific white shrimp (P. vannamei).