The effects of different levels of native commercial probiotic (Super zist) on the growth, nutritional efficiency and survival rate of Siberian sturgeon (Acipenser baerii) Juvenile

The use of selected bacteria to improve growth parameters and the microbial population in the host is one of the new ideas carried out for manipulating the bacterial population in aquatic organisms. These bacteria also consumed in the diets of farmed fish to optimize the balance of the microbial population of the gastrointestinal tract and they have a great effect on the growth and survival provides them. This study aimed to investigate the effect of commercial aquaculture probiotic (CA probiotic, Superzist, Zistyar Varna, Iran) on the growth performance and survival of juvenile of Siberian sturgeon. A number of 120 of Acipenser baerii with average of weight (109.3±3.7 g) were randomly distributed to 12 fiberglass tank containing 350-liter fresh water and 10 fish per tank. Fish were fed 2-3% body weight three times daily for 63 days. The CA probiotic comprising Bacillus subtilis, Lactobacillus acidophilus, L. delbrueckii, L. rhamnosus, L. plantarum in amount of 100, 200 and 300 mg/kg were added to basal diet (4mm pellets, Skretting, Italy). At the end of experiment, the survival rate of fish in the treatments were 100% and there were no significant difference in the treatments (P>0.05). There were no change in SGR in the treatments. Biomass increase, WG and BWI were increased and FCR and PER were decreased by increasing the amount of CA probiotic in the diet but there were no significant (P>0.05).