Aquaculture Reports (Aug 2023)
Feasibility evaluation of fermented peanut meal to replace soybean meal in the diet of common carp (Cyprinus carpio): Growth performance, serum biochemistry, intestinal health and microflora composition
Abstract
The effectiveness of soybean meal (SBM) substitution with fermented peanut meal (FPM) were appraised in common carp juveniles. A diet containing 30 % SBM was perceived as the control diet, then 25 %, 50 %, 75 % and 100 % of SBM was replaced by the FPM (FPM0, FPM25, FPM50, FPM75, FPM100 groups). Each group was fed to three replicate groups of common carp (4.83 ± 0.02 g) for 56 days. Results exhibited that FPM50 group attained the significantly higher mass gain rate and specific growth rate than those of the other groups except for FPM25, higher protein efficiency ratio and lower feed conversion rate than those of the FPM75 and FPM100 groups. The FPM50 group significantly increased the contents of serum total protein and albumin and decreased the content of serum urea nitrogen. The activity of hindgut protease was significantly enhanced in the FPM50 group. Significantly higher and lower intestinal villi height was, respectively, observed in the FPM50 and FPM100 group. The FPM50 group significantly enhanced the gene expression and activities of antioxidant enzymes in the intestine, reversely decreased the content of malonaldehyde. Significant increments in the occludin, myosin light chain kinase and claudin3 gene expressions in the FPM50 group improved the increase of intestinal permeability induced by pro-inflammatory factor related genes interleukin 1β, interleukin 6 and tumor necrosis factor α. Staphylococcus and Enterococcus in the intestine abundances were effectively suppressed in the FPM50 group, and Lactococcus became the dominant intestinal bacteria genera. The optimum substitution level was estimated to be 50.93 % and 49.89 % using broken-line regression analyses based on MGR and FCR. Overall, the soybean meal in common carp feed could be substituted up to 50 % by FBM without negative influence on growth, feed utilization and intestinal health.
