Effects of dietary replacement of fish meal by soybean meal on growth, feed utilization, and health condition of stinging catfish, .

Soybean meal (SBM) is a cost-effective alternative protein source to replace costly fish meal in aquaculture. This present study determined to measure the effects of replacing fish meal (FM) protein with SBM on growth, feed utilization, and health condition of stinging catfish, . Four isonitrogenous (35 %) diets were applied in four treatment groups designed as SBM, SBM, SBM, and SBM, where 0 %, 25 %, 50 %, and 75 % of FM protein were substituted by SBM, respectively. Significantly higher mean final weight (g), weight gain (g), percent weight gain (%), specific growth rate (% day), and protein efficiency ratio (PER) were recorded in SBM, SBM, and SBM groups than SBM group. Consequently, significantly lower feed conversion ratio (FCR) was found in SBM, SBM, and SBM groups than SBM group. Moreover, protein content of whole-body carcass was significantly higher in SBM and lower in SBM group however, lipid content was significantly higher in SBM and SBM than in other groups. Hemoglobin, red blood cells, and white blood cells were significantly higher in SBM, SBM, and SBM groups compared to SBM. However, the higher the substitution of FM protein by SBM in diets higher the values of glucose. Morphological analysis of the intestine including villi length (μm), width (μm), and area (mm); crypt depth (μm); wall thickness (μm); abundance of goblet cell (GB); and muscle thickness (μm) showed an increasing trend in fish fed diet containing upto 50 % replacement of FM protein by SBM. Therefore, the results suggest that SBM could replace upto 50 % FM protein in diets of  without compromising growth, feed efficiency, and health status.