Effect of Dietary A-Max Supplementation As A Prebiotic on Growth Performance and Hemato- Immunological Parameters of Great Sturgeon (Huso Huso Linnaeus, 1758) Juveniles

An 8-week feeding trial was conducted to evaluate the effects of dietary commercial prebiotic a-max, a mixture of mannan oligosaccharides, fructo oligosaccharides and β glucan, on growth and hemato-immunological parameters of great sturgeon (huso huso) juveniles. after acclimation, fish (initial weight of 28.79±0.85 g) were placed into 12 tanks (30 fish per tank). fish were fed a basal diet (containing 44% protein and 20% lipid) supplemented with 0 (control), 0.5, 1.0 and 1.5 g kg^-1 a-max in a totally randomized design in triplicate groups. at the end of the trial, growth factors and haemato-immunological parameters were assessed. fish fed 1.5 g kg^-1 prebiotic mixture displayed higher growth performances and feed efficiency compared to the control group (p>0.05). there were no significant differences in survival rate among all treatment groups (p>0.05). the results showed that rbc, wbc, lymphocyte, neutrophil, haematocrit and total protein were significantly affected by 1.5 g kg^-1 dietary prebiotic mixture (p<0.05). an elevation of monocyte and haemoglobin (p>0.05) was found in the fish fed diet containing 1.0 g kg^-1 prebiotic. in addition fish fed the diet with 1.5 g kg^-1 prebiotic mixture showed a significant increase in lyzosyme activity, respiratory burst activity, serum total immunoglobulin (ig) and alternative complement activity (ach50) (p<0.05) compared with those fed the diets supplemented with other levels of prebiotics. the results showed that the addition of 1.5 g kg^-1 prebiotic mixture to the diet of great sturgeon juveniles improving growth performance, some haematological parameters and immune response and seemed to be an effective immunostimulant.