The Changes Of Immunity And Quality In Sea Cucumber(Apostichopus Japonicus) By Dietary Rhodotorula Mucilaginosa Supplementation

In recent years,increased demand and the farming scale expands unceasingly of sea cucumber has leaded to a series of problem,such as low survival rate,growth retardation and weakened immunity.It has caused the huge impact to the development of aquaculture.Rhodolorula enhanced the animal immunity and improved the quality of its products as a feed additive.Rhodolorula mucilaginosa is a kind of saccharomyces,its application in aquaculture especially in the sea cucumber breeding research is less.Based on sea cucumber as the research object,this paper studies dietary Rhodotorula mucilaginosa 107 CFU/g,which impact on immunity and quality in sea cucumber.The main contents are as follows:Rhodotorula mucilaginosa was analyzed of the nutrition composition before feeding experiment.The results show that the crude protein mass fraction was 57.37%,unsaturated fatty acids accounted was 82.03%.Additionally,it was rich in glucan,?-carotene and vitamin E,the mass fraction respectively was 3.41%,17.05 mg/kg and 535.54 mg/kg.Proteomics analysis of sea cucumber coelomic fluid were based on two-dimensional electrophoresis and mass spectrometry.Study the effect on coelomic fluid immune proteins by dietary Rhodotorula mucilaginosa.Results indicate that a total of 60 protein spots were differentially expressed in the two groups.45 protein spots were expressed highly in blank control group,while 15 protein spots were expressed highly in experimental group.42 protein spots were successfully identified by mass spectrometry.Four of them are immune related proteins.Through the using of high-throughput sequencing technology and real-time quantitative PCR technology,studied the influence of intestinal microbiota and immune genetic in sea cucumber by dietary Rhodotorula mucilaginosa.The results showed that dietary Rhodotorula mucilaginosa supplementation can significantly improve the relative abundance of the sea cucumber intestinal microbiota.And it could promote the multiplication of beneficial bacteria and inhibit the growth of harmful bacteria.Dietary Rhodotorula mucilaginosa supplementation has a positive impact on immune responses of the intestine in sea cucumber by activating NF-?B signaling pathway.It could increase the relative expression level of TLR3,TRAF6,Lys,p105 and Rel in the intestinal tissue of sea cucumber.By measuring body wall structure,basic nutrients,amino acids and fatty acid composition,mineral element content,polysaccharide monosaccharide composition and content of body wall,studied the effect on products quality of sea cucumber by dietary Rhodotorula mucilaginosa supplementation.It shows that dietary Rhodotorula mucilaginosa supplementation could significantly increase the crude protein,polyunsaturated fatty acids,mineral elements,and can significantly improve structure features of sea cucumber.Amino acid composition,monosaccharide composition of polysaccharides had a certain influence.Above all,Rhodotorulamucilaginosa is rich in nutrients which is a kind of high quality feed additives.It can improve immunity,the structure of intestinal microbiota and the product quality in sea cucumber.