Impacts Of Fructo-Oligosaccharide And Bacillus Spp On Hybrid Tilapia’s Growth Performance And Non-Specific Immunity Function

The experiment was conducted to investigate the impact of the basal diets supplemented with different concentrations of fructooligosaccharides (FOS), bacillus spp, synbiotics and antibiotics on hybrid tilapia’s growth performance, serum non-specific immune index, and serum biochemical indexes.In the experiment,840hybrid tilapia with the average weight of11g were randomly divided into ten treatments, and three replicates per treatment, with28fish in each replicate. The control group was fed on the basal diet, while the remaining9trial groups as follows:Fructooligosaccharide Group I and II fed on the basal diet supplemented with0.1%and0.2%FOS; Bacillus Group I and II bred on the basal diet supplemented with0.1%and0.2%Bacillus subtilis bacillus; Synbiotics Group Ⅰ、Ⅱ、Ⅲ、Ⅳ fed on the basal diet supplemented with0.1%FOS and0.1%Bacillus subtilis bacillus、0.1%FOS and 0.2%Bacillus subtilis bacillus、0.2%FOS and0.1%Bacillus subtilis bacillus and0.2%FOS and0.2%Bacillus subtilis bacillus; Antibiotic Group fed on the basal diet supplemented with100mg/kg chlortetracycline. The experiment lasted for56days to investigate the effect of the basal diet supplemented with different concentrations of fructooligosaccharides (FOS), Bacillus spp, synbiotics and antibiotics on the growth performance, serum non-specific immune index and serum biochemical indexes of hybrid tilapia.The results of growth performance showed that, compared with the control group, the weight gain rate of hybrid tilapia was increased and its feed conversion rate was decreased in the9trial groups. Among them, hybrid tilapia’s weight gain rate in Synbiotics Group Ⅰ、Ⅱ、Ⅲ and the Antibiotic Group was significantly higher than the control group (P<0.05), respectively, to69.06%,94.29%,46.90%,58.69%, while hybrid tilapia’s feed conversion rate in Synbiotics Group Ⅰ、Ⅱ、Ⅲ and the Antibiotic Group was significantly lower than the control group (P<0.05), respectively decreased30.30%,33.33%,21.97%,19.70%,25.76%. In short, the weight gain rate of hybrid tilapia were significant increases (P<0.05) and feed conversion rate significant were decreased (P<0.05)in these groups, with the highest increased the weight gain rate and the lowest decreased feed conversion rate in Synbiotics Group Ⅱ.The results of serum non-specific immune index also showed that, compared with the control group, the tilapia serum superoxide dismutase (SOD), serum lysozyme (LSZ), serum acid phosphatase (ACP) activity in the9trial groups were improved,Among them, hybrid tilapia’s serum SOD activity in Synbiotics Group Ⅰ、Ⅱ、Ⅲ、Ⅳ was significantly higher than the control group (P<0.05), serum LSZ activity in Synbiotics Group Ⅰ、Ⅱ was significantly higher than control group (P<0.05), and serum ACP activity in the9trial groups was significantly higher than control group (P<0.05). The serum SOD, serum LSZ, serum ACP activity of hybrid tilapia were significant increased in Synbiotics Group Ⅰ、Ⅱ, with the most significant effect in Synbiotics Group Ⅱ.The test results demonstrated, there was no significant difference in serum total protein (TP) and serum albumin (ALB) between the9trial groups and control group (P>0.05). The serum alanine aminotransferase (ALT) activity in Bacillus Group Ⅰ, Synbiotics Group Ⅲ and the Antibiotic Group was significantly higher than that of control group (P<0.05), the aspartate aminotransferase (AST) activity in Fructooligosaccharide Group Ⅰ, Bacillus Group Ⅰ, Bacillus Group Ⅱ, Synbiotics Group Ⅲ, Synbiotics Group IV and the Antibiotic Group was significantly higher than the control group (P<0.05), and there was no significant effect on ALT and AST activity in Fructooligosaccharide Group Ⅱ, Synbiotics Group I and Synbiotics Group Ⅱ.The experiment showed no significant difference in the alkaline phosphatase (ALP) activity between the9non-control groups and control group (P>0.05), and the ALP activity in Synbiotics Group Ⅰ, Synbiotics Group Ⅱ and the Antibiotic Group was higher than the control group, with the highest in Synbiotics Group Ⅱ. The serum urea nitrogen (BUN) in Bacillus Group I, Synbiotics Group Ⅲ、Ⅳ and the Antibiotic Group were significantly higher than control group (P<0.05), and there was the lowest the serum BUN content in Synbiotics Group II. The experiment showed no significant difference in the a serum total cholesterol (T-CHO) between the9trial groups and control group(P>0.05), and there was the lowest serum T-CHO content in Synbiotics Group Ⅱ. The serum triglyceride (TG) in Synbiotics Group Ⅲ and Synbiotics Group IV were significantly higher than the control group (P<0.05), and there was the lowest serum triglyceride (TG) content in Synbiotics Group Ⅱ, which mean the serum triglyceride (TG) content in Synbiotics Group Ⅱ was lower than that in the control group.In conclusion, The growth performance and serum non-specific immune index of hybrid tilapia fed basal diet supplementation with single FOS and BS were inproved in some degree,but the function is less than the mixed FOS and SYB. Synbiotics Group Ⅱ played a significant role in hybrid tilapia’s growth and immunity, the function is the same as the AM Group and much better than other groups, so it could be recommended as feed additive.