Effect Of Dietary Supplementation Of Bacillus Subtilis JS01and Astragalus Polysaccharide On The Growth Performance And Immunity Function Of Jian Carp (Cyprinus Carpio Var. Jian)

The aim of this present paper is to study the effects on the growth and immune function of Jian carp feeding dietary supplementation Bacillus subtilis or/and Astragalus polysaccharide, which is to study the effects of synbiotics (probiotics and polysaccharide) on the growth and immune function of Jian carp.Test1:240healthy carp (50.2±2.1g) was individed into4groups (A, B, C, D). The control group (group A) was feed with a basal diet. The group B was feed with a basal diet supplemented with B. subtilis JS01(2×107CFU g-1, feed). The group C was feed with a basal diet supplemented with APS (500mg kg-1, feed,50%pure). The group D was feed with a basal diet supplemented with both B. subtilis JS01(2×107CFU g-1, feed) and APS (500mg kg-1, feed). After feeding for14d,28d,42d, the body weight gain (%), the activity of amylase, lipase and trypsin in the middle intestine, the concentration of C3, C4and IgM, the activity of LZM and SOD in the serum were detected; at42d, the flora diversity in the intestine, the expression of immune genes IL-1β, LZM-C and IL-8were analyzed.Test2:120healthy carp (10.1±1.2g) were divided into four groups which were feed the four kind of dietary. After42days feeding, all the carp were intraperitoneally challenged with0.3ml fresh culture suspension containing6×108CFU/mL Aeromonas hydrophila, and15days later the survival rate was recorded.Results:1. Body weight gain (%) and the survival rate:After feeding for42days, the weight gain of group B and C was significantly greater than that of group A and D(p<0.05), and significant differences between Group A and D were not observed. The survival rate of carp in group B, C and D were significant than that in group A(p<0.01); and the survival rate of carp in group B and C were significant than that in group D(p<0.01). The results show that dietary supplementation with B. subtilis JS01or APS can improve the body weight gain and survival rate of Jian carp; and the single addition is better than the synbiotics.2. The digestive enzyme activity:at14d,28d and42d, the amylase activity in group B were extremely significantly higher than that in A and C and D group(p<0.01); the amylase activity in group D was only significant higher than that in group A and C(p<0.05), and the rest of the time points were no differences. At14d,28d and42d, the lipase activity in group B, C and D were significantly higher than that in group A(p<0.01). At14d and28d, the trypsin activity in the group D was significantly lower than that in group A, B, and C, whereas group B were significantly higher than that in group A and C(p<0.01); at42d, activity of trypsin in group B was very significantly higher than A, C, D, whereas group C was significantly lower than that in group A(p<0.01). The results show that dietary supplementation with B. subtilis JS01or APS can improve the digestive enzyme activity of Jian carp; and the single addition is better than the synbiotics.3. Intestinal flora diversity:at42d, the additives had a greater influence on the intestinal flora of carp. The dominant flora in group B, C and D increased6,5and2, respectively; compared with group A, the similarity coefficient in group B, C and D were57%,56%and57%respectively; compared with group B, the similarity coefficient in group C and D were56%and73%, respectively; the similarity coefficient between group C and D was56%. The results show that dietary supplementation with B. subtilis JS01or APS can improve the intestinal flora diversity of Jian carp; and the single addition is better than the synbiotics.4. Immune parameters in serum:the concentration of C3in the four groups was not significantly different after feeding for14and28days; however, the concentration of C3in group B was significantly higher than that of group D after42days(p<0.05). The concentration of C4in group B was significantly higher than that of group D after feeding for14days, and the C4concentration of Group D was significantly lower than that of group B and C after feeding for28,42days(p<0.05). Significant differences in the concentration of IgM among the four groups were not observed after14days for feeding. The IgM concentration of Group B was significantly higher than that of group A (p<0.05)and was extremely higher than that of group D after28days for feeding(p<0.01). The IgM concentration of group D was significantly lower than that of group A, B and C after28days and42days for feeding (p<0.05). The LZM activity of group B and C were extremely different than that of group A and D(p<0.01); however, significant differences in the LZM activity were not observed among group B and C. The LZM activity of group D was significantly higher than that of group A after feeding for14days(p<0.01). Nevertheless, as the feeding time increased, significant differences in the LZM activity were no longer detected. After feeding for28days and42days, the SOD activity of group D was significantly lower than that of group A, B and C(p<0.01). The results show that dietary supplementation with B. subtilis JS01or APS can improve the immune parameters in serum of Jian carp; and the single addition is better than the synbiotics.5. Expression of immune-related genes:at42d, the expression of IL-1β in head kidney of group B and C were significantly higher than that in group A and D(p<0.05); and no significant difference was existed between groups A and D. The expression of LZM-C in head kidney of group B, C and D were significantly higher than that in group A(p<0.05), and the expression of LZM-C in group B was significantly higher than that in group C and D(p<0.05), but no significant difference between group C and D was existed. The expressions of IL-8in the four groups were significant difference(p<0.05); and the expression of IL-8in group B was successively higher than that in group C, A and D(p<0.05). The results show that dietary supplementation with B. subtilis JSO1or APS can improve the expression of immune-related genes of Jian carp; and the single addition is better than the synbiotics.Conclusion:Dietary supplementation with B. subtilis JS01(2×107CFU g-1) or APS (500mg kg"’)can improve the growth performance and immune function of Jian carp; the synbiotics, B. subtilis JS01(2×107CFU g-1) and APS (500mg kg-1), can improve the growth performance and immune function of Jian carp, too; but single addition is better than the synbiotics.