Vol. 9, Issue 12, Part E (2025)

The present study was conducted to evaluate the effects of dietary supplementation of fructooligosaccharide (FOS) on growth performance, survival rate, feed utilization and disease resistance against Aeromonas hydrophila in Labeo rohita. The experiment was carried out for 60 days at the College of Fisheries Science, Kamdhenu University, Veraval, using a Completely Randomized Design (CRD) with five treatments and four replicates each. Experimental diets were formulated with 0% (control), 0.5%, 1%, 1.5% and 2% FOS inclusion levels. Results revealed that FOS supplementation significantly (p<0.05) enhanced growth and feed utilization parameters compared to the control. The highest performance was observed in the 2% FOS-supplemented group (T4), which recorded the greatest mean weight gain (2.64±0.039 g), specific growth rate (3.06±0.006%) and lowest feed conversion ratio (2.26±0.017). Protein efficiency ratio and feed conversion efficiency were also markedly improved in the FOS-treated groups. Following the disease challenge with A. hydrophila, survival rate increased progressively with FOS inclusion, reaching a maximum of 80% in the 2% FOS group. Throughout the study, water quality parameters remained within optimal ranges for L. rohita culture. Overall, the findings demonstrate that dietary inclusion of 2% fructooligosaccharide effectively improves growth performance, feed utilization efficiency and disease resistance in Labeo rohita. Thus, FOS can be considered a promising prebiotic additive for sustainable aquaculture, enhancing fish health and productivity while reducing reliance on antibiotics.