We investigated the effects of Lactobacillus plantarum used as a dietary supplement on the growth performance and innate immune response in juvenile Siberian sturgeon Acipenser baerii. Juvenile fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 10(7), 1 × 10(8) and 1 × 10(9) colony-forming units (cfu) g(-1)] and a control (non-supplemented basal) diet for 8 weeks. Growth performance indices were increased in fish fed the 1 × 10(8) cfu g(-1) L. plantarum diet compared to the other groups. There was an increased innate immune response in fish fed the experimental diets. The highest levels of lysozyme activity, total immunoglobulin (IgM) and complement component 3 (C3) were observed in fish fed the diet containing L. plantarum at a concentration of 1 × 10(8) cfu g(-1), but there was no significant difference in the level of complement component 4 (C4) in fish fed the experimental diets or the control diet. The present study underlying some positive effects (growth performance and immune indices) of dietary administration of L. plantarum at a concentration of 1 × 10(8) cfu g(-1) in the Siberian sturgeon.

A feeding trial was conducted to investigate the effects of different levels of dietary Lactobacillus plantarum on hemato-immunological parameters and resistance against Streptococcus iniae infection in juvenile Siberian sturgeon Acipenser baerii. Fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 10, 1 × 10 and 1 × 10 colony-forming units (cfu) g] and a control (non-supplemented basal) diet for 8 weeks. Innate immune responses (immunoglobulin (Ig), alternative complement activity (ACH50) and lysozyme activity) were significantly higher in fish fed the 1 × 10 and 1 × 10 cfu g L. plantarum diet compared to the other groups (P < 0.05). Furthermore, fish fed on various levels of L. plantarum significantly showed higher red blood cell (RBC), hemoglobin (Hb), white blood cell (WBC) and monocyte compared to those of the control group (P < 0.05). At the end of the feeding experiment, some fish were challenged with S. iniae to quantify the level of disease resistance. The mortality after S. iniae challenge was decreased in fish fed a probiotic. These results indicated that dietary supplementation of L. plantarum improved immune response and disease resistance of Siberian sturgeon juvenile.

The current study was carried out to evaluate the effects of probiotic, Lactobacillus plantarum on growth performance and hematological parameters in Siberian sturgeon (Acipenser baerii). Fish (14.6±2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations (1×10 7 , 1×10 8 and 1×10 9 colony-forming units (cfu) g -1 ) and a control (non-supplemented basal) diet for 8 weeks. At the end of the experiment, 3 fish were sampled randomly from each tank and were anaesthetized. Then, blood samples were introduced to heparinized tubes in order to perform performance and hematological studies. Growth performance indices were increased in fish fed the 1×10 8 cfu g -1 L. plantarum diet compared to the other groups. Furthermore, the fish fed on various levels of L. plantarum significantly showed higher red blood cell, hemoglobin, white blood cell and monocyte compared to those of the control group (P<0.05). Although, the effect of probiotic treatments on other hematological parameters were not significant (P>0.05); but this value was higher in probiotic supplement treatments compared to control group. These results indicated that dietary supplementation of L. plantarum improved growth performance and hematological parameters in Siberian sturgeon.