High carbohydrate to protein ratio promotes changes in intestinal microbiota and host metabolism in rainbow trout (Oncorhynchus mykiss) fed plant-based diet

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: May 2, 2023

Abstract To ensure the sustainability of aquaculture, it is necessary to change “menu” carnivorous fish such as rainbow trout from a fish-based diet one with plant-based ingredients. However, there major problem growth performance decrease fed 100% due reduction in feed intake and efficiency. For first time, we incorporated high levels digestible carbohydrates (high-starch diet) during 12-week feeding trial order improve protein utilization for (protein sparing effect) reduce nitrogen waste. We measured changes intestinal microbiota, Short-Chain Fatty Acid (SCFA) metabolic responses liver. Dietary had strong effect on alpha beta diversity abundance 12 genera, including Ralstonia Bacillus digesta associated microbiota whereas mucosa was less affected. The microbial might be linked observed SCFA production. High Mycoplasma were mucosa. Overall, hepatic gene expression significantly altered by CHO/protein ratio. Up-regulation genes involved glucose metabolism ( gcka , gckb g6pcb2a ), down-regulation lipid hadh acox3 srebp2a cyp51a ) higher enzymatic activities (such glucokinase or pyruvate kinase) glycogen liver, suggesting adequate adaptation diet. Interestingly, correlations between abundances certain bacterial OTUs inclusion combination diet, could promising way use plant proteins trout. In addition, relationship host needs further investigation better understand nutrition.

Language: Английский

DNA from non-viable bacteria biases diversity estimates in the coralsAcropora loripesandPocillopora acuta

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Nov. 17, 2023

Abstract Background Nucleic acid-based analytical methods have greatly expanded our understanding of global prokaryotic diversity, yet standard metabarcoding provide no information on the most fundamental physiological state bacteria, viability. Scleractinian corals harbour a complex microbiome in which bacterial symbionts play critical roles maintaining health and functioning holobiont. However, coral holobiont contains both dead living bacteria. The former can be result feeding rapid swings from hyper- to hypoxic conditions tissue, presence antimicrobial compounds mucus, an abundance lytic bacteriophages. Results By combining propidium monoazide (PMA) treatment with high-throughput sequencing six species ( Acropora loripes , A. millepora kenti Platygyra daedalea Pocillopora acuta Porites lutea ) we were able obtain communities little noise non-viable microbial DNA. Metabarcoding 16S rRNA gene showed significantly higher community evenness (85%) diversity (31%) untreated compared PMA-treated tissue for only. While did not differ samples terms observed number ASVs, >30% ASVs identified only, suggesting that they originated cell-free/non-viable Further, structure was different between P. indicating DNA microbes bias composition data low diversity. Conclusions Our study is highly relevant studies other host organisms as it delivers solution excluding community. These results novel insights into dynamic nature host-associated microbiomes underline importance applying versatile tools analysis or next-generation sets.

Language: Английский