Effect of dietary synbiotic on serum biochemistry and anti-oxidative function of Labeo rohita fingerlings exposed to sub-lethal nitrite stress.

Abstract

A 60-days feeding trial was conducted to evaluate the of supplementation of Bacillus circulans (BC) and a prebiotic fructooligosaccharide (FOS), applied alone or mixed in diet of Labeo rohita (rohu) and its effects on the serum profile [total protein, albumin (A), globulin (G), A/G ratio] and antioxidant stress enzymes [superoxide dismutase (SOD), catalase, glutathione S transferase (GST)]. Fish were fed diet containing combinations of BC and FOS namely control (0% BC+0% FOS), T1 (106 cfu/g BC), T2 (108 cfu/g BC), T3 (1% FOS), T4 (2% FOS), T5 (106 cfu/g BC+1%FOS), T6 (106 cfu/g BC+2% FOS), T7 (108 cfu/g BC+1% FOS) and T8 (108 cfu/g BC+2% FOS). Total protein was elevated in supplemented groups, and highest observed in T5 group. Groups fed BC alone or mixed showed higher globulin levels, whereas 2% FOS lowered globulin level. A/G ratio decreased except in T4 and T8. Activity of antioxidant enzymes showed low levels in treated groups in comparision to control, with T4 exhibiting significantly lowest (P<0.05). Overall results from this study indicate the potential of using dietary BC and FOS in mixture for an improved immune function; however 2% FOS suppressted the serum profile and digestive function of rohu juveniles.