文献类型：期刊文献

中文题名：饲料中添加β-葡聚糖对珍珠龙胆石斑鱼生长性能、免疫指标、转录组及肠道菌群的影响

英文题名：Effects of addingβ-glucan to feed on the growth performance,immune indexes,transcriptome and intestinal flora of Epinephelus fuscoguttatus♀×Epinephelus lanceolatus♂

作者：陈俭[1];代冰涛[1];王红明[1];宋守钢[1];谭北平[1,2];章双[1,2]

机构：[1]广东海洋大学水产动物营养与饲料实验室,广东湛江524088;[2]农业农村部华南水产与畜禽饲料重点实验室,广东湛江524088

年份：2022

卷号：53

期号：5

起止页码：1434

中文期刊名：南方农业学报

外文期刊名：Journal of Southern Agriculture

收录：CSTPCD、、北大核心、CSCD、北大核心2020、CSCD_E2021_2022

基金：国家重点研发计划项目(2019YFD0900200);国家现代农业产业技术体系建设专项(CARS-47)。

语种：中文

中文关键词：珍珠龙胆石斑鱼;β-葡聚糖;生长性能;免疫能力;转录组;肠道菌群

外文关键词：E.fuscoguttatus♀×E.lanceolatus♂;β-glucan;growth performance;immunity;transcriptome;intestinal bacteria community

中文摘要：【目的】明确β-葡聚糖诱导珍珠龙胆石斑鱼的免疫响应机制,为β-葡聚糖作为免疫增强剂在水产饲料中的应用提供理论依据。【方法】以珍珠龙胆石斑鱼为研究对象,通过在饲料中添加100 mg/kgβ-葡聚糖进行养殖试验,饲养8周后采样分别进行生长性能、血清生化指标、转录组测序和肠道菌群组成分析。【结果】饲料中添加β-葡聚糖显著提高珍珠龙胆石斑鱼的终末体重、增重率和特定生长率(P<0.05,下同),并降低脏体比。与对照(基础饲料)组相比,β-葡聚糖添加组珍珠龙胆石斑鱼血清总蛋白含量及过氧化氢酶、溶菌酶、胃蛋白酶和肠脂肪酶活性显著升高,而总甘油三酯含量、总胆固醇含量、谷丙转氨酶活性及丙二醛含量呈显著降低趋势。转录组测序结果显示,共组装获得79291条Unigenes,平均长度为941 bp;依据FDR≤0.05且|log2FC(Sample2/Sample1)|≥1的筛选条件,共筛选获得8014个差异表达基因(4990个上调基因和3024个下调基因);KEGG信号通路富集分析发现有648个差异表达基因被富集到175个KEEG信号通路上,其中有16条通路与免疫功能相关,涉及139个显著差异基因。HiSeq PE250高通量测序分析结果显示:β-葡聚糖组珍珠龙胆石斑鱼肠道菌群OUTs数量、ACE指数和Shannon指数显著高于对照组,Chao1指数和Simpson指数无显著差异(P>0.05)。在门分类水平上,珍珠龙胆石斑鱼肠道菌群中以变形菌门、放线菌门拟杆菌门、蓝藻门及厚壁菌门为优势菌群,β-葡聚糖组中变形菌门和蓝藻门的相对丰度显著低于对照组,厚壁菌门和拟杆菌门的相对丰度则极显著高于对照组(P<0.01,下同);在属分类水平上,以发光杆菌属、鞘氨醇单胞菌属、盐单胞菌属、红游动菌属及无色杆菌属为优势菌群,且表现为β-葡聚糖组中发光杆菌属的相对丰度显著低于对照组,盐单胞菌属的相对丰度极显著低于对照组。【结论】β-葡聚糖能有效增强珍珠龙胆石斑鱼的抗氧化能力及提高其肠道菌群物种丰度和多样性以抵御外界有害菌的繁殖,同时提升珍珠龙胆石斑鱼的抗炎症和抗病等免疫能力。即β-葡聚糖在珍珠龙胆石斑鱼上具有良好的生长和免疫增强效果,可作为新型免疫增强剂推广应用。

外文摘要：【Objective】To clarify the immune response mechanism induced byβ-glucan in Epinephelus fuscoguttatus♀×Epinephelus lanceolatus♂,so as to provide a theoretical basis for the application ofβ-glucan as an immune enhancer in aquafeed.【Method】Taking E.fuscoguttatus♀×E.lanceolatus♂as the research object,the breeding experiment was carried out by adding 100 mg/kgβ-glucan to the feed.After 8 weeks of feeding,samples were collected for growth performance,serum biochemical indicators,transcriptome and intestinal bacteria community analysis.【Result】Addingβ-glucan to feed significantly increased the final body mass,weight gain rate and specific growth rate(P<0.05,the same below),and decreased the liver-body weight ratio.Total protein content in serum,the activities of catalase,lysozyme,pepsin and intestinal lipase in the grouper withβ-glucan were significantly higher than those in the control group,and total triglyceride content,total cholesterol content,glutamic pyruvic transaminase activity and malondialdehyde content decreased significantly.Transcriptome sequencing results showed that 79291 unigenes were assembled,with an average length of 941bp;according to the screening condition of FDR≤0.05 and|log2FC(Sample2/Sample1)|≥1,a total of 8014 differentially expressed genes(DEGs)were obtained(4990 up-regulated genes and 3024 down-regulated genes);648 DEGs were found to be enriched on 175 KEEG signaling pathways by KEGG signal pathway enrichment analysis,and there were 16pathways associated with immune function,involving 139 significantly differential genes.The results of HiSeq PE250high-throughput sequencing analysis showed that the number of intestinal bacteria community OUTs,ACE index and Shannon index in theβ-glucan-adding group of E.fuscoguttatus♀×E.lanceolatus♂were significantly higher than those in control group.There was no significant difference in Chao1 index and Simpson index(P>0.05).At the phylum level,Proteobacteria,Actinomycetes,Bacteroidetes,Cyanobacteria and Firmicutes were the dominant bacteria communities for E.fuscoguttatus♀×E.lanceolatus♂.In theβ-glucan-adding group;the relative abundances of Proteobacteria and Cyanobacteria were significantly lower than those in control group.while the relative abundances of Firmicutes and Bacteroidetes inβ-glucan group were significantly higher than those in control group(P<0.01,the same below).At the genus level,the dominant bacteria communities were Photobacterium,Sphingosphingomonas,Halomonas,Rhodoplanes and Achromobacter;the relative abundance of Photobacterium inβ-glucan-adding group was significantly lower than that in the control group and the relative abundance of Halomonas was significantly lower than that of the control group.【Conclusion】β-glucan can effectively enhance the antioxidant ability of E.fuscoguttatus♀×E.lanceolatus♂and improve the species richness and diversity of its intestinal bacteria communities to resist the reproduction of external harmful bacteria.At the same time,β-glucan can improve immunity of E.fuscoguttatus♀×E.lanceolatus♂to resist diseases and inflammation.That is,β-glucan has positive effect on growth and immunity enhancement on E.fuscoguttatus♀×E.lanceolatus♂,and it can be popularized and applied as a new type of immunity enhancer.