Abstract

This research was done on Channa punctata to evaluate the effects of dietary Bacillus subtilis on some on the growth and some physiological activities. 120 healthy fish with 21.3 ± 2.5 g transferred into12 aquaria and fed four diets: a control (0 g/kg) 3, 6, and 9 g/kg B. subtilis per kg feed for 90 days.  The enhancements in growth parameters, with the highest final body weight was 104.4 ± 1.37 g and feed conversion ratio; 1.245 ± 0.0085 recorded in the 9 g/kg group. Lipid profiles also enhanced, with decreased triglycerides (101.2 ± 4.7 mg/dl, p = 0.0009) and improved high-density lipoprotein (HDL) (67.4 ± 2.33 mg/dl, p = 0.0003) in the 6 g/kg group. Digestive enzyme activity (lipase: 131.6 ± 3.57 U/L, p < 0.0001) and antioxidant responses (reduced catalase activity: 10.62 ± 0.2 U/mg, p < 0.0001) were similarly enhanced. This study concluded that Bacillus subtilis at 6–9 g/kg enhances growth, lipid metabolism, and oxidative stress resistance in C. punctata, regarded its use as a sustainable aquafeed additive.

Keywords: Antioxidant, Bacillus subtilis, Channa punctata, Growth performance, Lipid profile