Effect of Dietary Supplementation of Probiotics As Immunostimulants on Growth Performance, Immune Responses and Intestinal Flora of Japaness Sea Bass (lateolabrax Japonicus)
|School||Chinese Academy of Agricultural Sciences|
|Course||Animal Nutrition and Feed Science|
|Keywords||Flower perch Galactooligosaccharides Raffinose Non-specific immune Anti-stress Aeromonas hydrophila Intestinal bacteria Diversity Dilution spread plate PCR-DGGE 16S rRNA|
Of this study two oligosaccharide galacto oligosaccharides and raffinose sugar carnivorous fish flowers perch (Lateolabrax japonicus) growth performance, blood biochemical indices of non-specific immunity, antioxidant, anti-Aeromonas hydrophila bacteria cumulative survival and intestinal microbial structure. Determine the optimal addition amount of the galacto-oligosaccharide and raffinose in the Lateolabrax feed, and both function as probiotics additives comparative study. This study consists of a five-part test, are summarized as follows: 1, the test is an evaluation the Ruyuan Probiotics galactooligosaccharides flower perch growth, immunity and resistance to Aeromonas hydrophila effect. Test A total of five treatment groups: 0 (control group), 20, 40, 80, and 200g/kg semi milk oligosaccharides; granulated ball machine rotated into each feed by extrusion. Three replicates each treatment, the initial weight of the flower perch 3g about test 260L fiber glass tank recirculating system. The trial lasted 16 weeks, 16 weeks after the end of the feeding trial, the air exposure test and hydrophila Aeromonas challenge test. The results show that, feed, add the 20g/kg galactooligosaccharides significantly improve the disease resistance of the flower perch (P lt; 0.05) hydrophila Aeromonas test group of fish survival rate was significantly higher after challenging (P lt; 0.05). 40g/kg and 80g/kg galactooligosaccharides group increased flower perch growth performance, but with the control group, there was no significant difference (P gt; 0.05). The 200g/kg flowers of the highest dose group perch serum malondialdehyde (MDA) was significantly higher than other groups (P lt; 0.05), said the fish higher levels of peroxide, which may be associated with higher feed protein content. Recommended to add 40 ~ 80g/kg galactooligosaccharides. In spend perch feed. 2, test two cumulative survival rate of raffinose flower perch growth, nonspecific immunity, anti-stress hydrophila Aeromonas attack poison. Basal diet was formulated according to the nutritional needs of sea perch. Test design five treatments, the amount of the raffinose feed add: 0 (control), 200, 400, 800 and 2000 mg / Kg respectively named R0, R200, R400, R800 and R2000. Each treatment three replicates of 30 fish (initial body weight about 3g). The trial lasted 16 weeks, weighed and serum samples for the determination of the immune and antioxidant indicators after the end of the trial. In addition respectively the the 30s air exposed to stress and hydrophila Aeromonas attack poison test. The results showed that the survival and feeding rate of each test group of sea perch no significant difference (P gt; 0.05); the R800 group weight gain was significantly higher than that of the control group, R400 and R2000 group (P lt; 0.05). R400 group feed conversion ratio was significantly higher than the R800 group (P lt; 0.05), protein efficiency while the R400 group was significantly lower than the R800 group (P lt; 0.05), but with other groups without significant differences. Protein deposition rate among the groups no differences (P gt; 0.05); each processing liver index did not significantly significant difference (P gt; 0.05); control group, R200 and R2000 fat full degree significantly with higher than R400 and R800 group (P lt ; 0.05); R800 group of sea perch viscera was significantly lower than the R400 group. Serum lysozyme, superoxide dismutase and oxidation product malondialdehyde content between the groups there was no difference. Serum glucose and cortisol after the the 30s air exposure stress did not show differences, but the tropic water vapor Aeromonas (Aeromonas hydrophila Hoshina) challenged control group cumulative survival rate was 65%, significantly lower than the test group. Raffinose flower perch feed suitable dosage 800mg/kg. 3 trials three through dilution spread plate method, count flowers perch intestinal bacteria isolated and cultured, as a feed additive analysis of of galacto oligosaccharides and raffinose flower perch intestinal microbial quantity and diversity. The results showed that the flowers perch intestinal bacteria starting number of 3.38 × cfu / g, 8 weeks after bacterial magnitude of 108 cfu / g; 16 weeks after the order of magnitude of the intestinal bacteria fed add galactooligosaccharides and raffinose 1011 cfu / g. 16 weeks, the control group was isolated 11 bacteria, 10 Pseudomonas, an Aeromonas. In the 16 weeks galactooligosaccharides test group G4 treated isolated seven bacterial 4 the Bacillus; G20 treated six bacteria isolated from two Aeromonas. Raffinose test group of 16 weeks, R200 treatment isolated 11 strains of bacteria, a Bacillus; the R2000 treatment isolated 17 bacteria, a Bacillus, an Aeromonas. Seen from the results of this test, the feed add 200mg/kg of raffinose and galactooligosaccharides 4g/kg conducive to the growth of Bacillus subtilis, and while suppressing the growth of Aeromonas. 4, test PCR combined with denaturing gradient gel electrophoresis (PCR-DGGE) technical analysis galacto-oligosaccharides as a feed additive fed early, 8 weeks and 16 weeks spent perch intestinal bacterial diversity. The intestinal bacterial 16S rDNA sequences characteristic fragment V3 region sequences DGGE After the rich diversity of bacteria in the intestinal contents of sea perch. The results show that, (1) 8 weeks, each test group can keep the native bacteria Pseudomonas colonization in the intestine, but by 16 weeks, Pseudomonas disappeared from the intestinal tract of all treatment groups; (2) In addition to the eight weeks G2 there are eight weeks of each treatment and 16 weeks treatment of sea perch intestinal gut Enterobacteriaceae Enterobacteriaceae; (3) from the initial 8 weeks and 16 weeks, G8 and G20 treatment group were able to promote native bacteria oligonucleotide raising Aeromonas bacteria in the gut colonization; (4) 16 weeks, G8 and G20 treated Klebsiella; (5) eight weeks, the processing of sea perch gut false Alteromonas sp, but to 16 weeks, only the test group intestinal isolated false Alteromonas bacteria seen each experimental group to promote this the exogenous fake alternating single-cell bacteria in the gut colonization. 5, the trial of five PCR combined with denaturing gradient gel electrophoresis (PCR-DGGE) analysis raffinose as a feed additive fed early, 8 weeks and 16 weeks flower perch intestinal bacterial diversity. The intestinal bacterial 16S rDNA sequences characteristic fragment V3 region sequences DGGE After the rich diversity of bacteria in the intestinal contents of sea perch. The results show that, (1) 8 circumferential addition R800 processing group of other processing, and 16 weeks all processing group are separated to the native bacteria false alternating single extracellular bacteria, visible, the feed add raffinose able to promote its in the gut colonization; flower perch (2) Add in the eight weeks of short-term feeding raffinose intestinal able to maintain the native bacteria oligotrophic Aeromonas and Pseudomonas colonization in the intestine, but up to 16 weeks, both genus each treatment group intestinal disappeared; (3) is added in the feed to be able to change the composition of the intestinal microflora of raffinose, Flavobacterium, and the presence of bacteria of the actinomycetes R800 treated never, therefore, to infer 800mg/kg The raffinose able to improve the intestinal microbial species.