A comparative study of beta glucan and plant stimulants on the growth, histology and immune response of Labeo rohita

Abstract

The experiment was conducted to evaluate the effect of beta glucan and plant extract (Vitabio A) and plant extract with probiotic Lactobacillus spp. (Vitabio B) on the growth, histology and immune response of Labeo rohita (Rohu), reared for 120 days in flow through system. Fish with an average body weight of 264±2.65g were stocked in cemented tanks at 10 fish/replicate. Four iso-nitrogenous artificial feeds containing 0.1% of beta glucan, plant extract, plant+probiotic and control (without any immunostimulants) were given at 3% body weight of fish twice a day. A significant (P<0.05) difference in weight gain was observed between the control and plant extract fed group while it was non-significant (P>0.05) for the other treatments. The total serum proteins and cell counts (CBC) showed non-significant (P>0.05) difference among all the treatments except RBCs and Hb which were found significantly higher in T1 (control)and T2(plant extract + bacteria Lactobacillus spp.) compared to T3(beta glucan) and T4(plant extract). The fish body composition analysis revealed that plant stimulant treatment significantly has the higher content of crude protein and ash contents followed by other treated groups and lower fat compared to control (T1). In conclusion, the plant extracts and beta glucan can be used without any adverse effect on the growth, total serum proteins, hematology and fish body composition.