肠道微生物群的表征和功能分析对于指导鱼类的营养干预和实现有利的宿主-微生物相互作用至关重要。因此,我们进行了为期30天的研究,以探索和记录O.niloticus的肠道微生物群落,以及通过基因组分析评估含有0.5%和0.75%芦荟提取物的基于多糖的益生元对肠道微生物组的影响。使用IlluminaHiSeq2500对16SrRNA的V3-V4区域进行扩增和测序,得出1,000,199个读数,用于操作分类单位(OTU)鉴定。在8,894个OTU中,选择1,181进行进一步分析。我们的结果显示,普朗克酵母,Firmicutes,变形杆菌,Verrucomicrobia,放线菌,在对照和处理样品中,镰刀菌是优势门。发现较高剂量的益生元可改善Planctomycetes和Firmicutes,同时减少Proteobacteria和Verrucomicrobia。我们观察到芽孢杆菌的丰度呈上升趋势,芽孢杆菌科,和类中的芽孢杆菌,家庭,和属水平,分别,以剂量依赖的方式。这些发现与常规菌落计数数据一致,这表明在补充益生元的组中芽孢杆菌的患病率较高。此外,使用PICRUSt进行的预测功能分析表明糖酵解V的剂量依赖性上调,乙二醇代谢和降解的超途径,葡萄糖和木糖降解,糖酵解II,和磺基糖酵解途径。大部分的能量,蛋白质,和氨基酸合成途径仅在较低剂量的益生元处理下上调。我们的发现表明,可以通过基于植物的多糖的营养干预来优化O.niloticus的肠道微生物组,以改善商品鱼的生长性能。
Characterization and functional profiling of the gut microbiota are essential for guiding nutritional interventions in fish and achieving favorable host-microbe interactions. Thus, we conducted a 30 days study to explore and document the gut microbial community of O. niloticus, as well as to evaluate the effects of a polysaccharide-based prebiotics with 0.5% and 0.75% Aloe vera extract on the gut microbiome through genomic analysis. The V3-V4 region of 16S rRNA was amplified and sequenced using Illumina HiSeq 2500, resulting in 1,000,199 reads for operational taxonomic unit (OTU) identification. Out of 8,894 OTUs, 1,181 were selected for further analysis. Our results revealed that Planctomycetes, Firmicutes, Proteobacteria, Verrucomicrobia, Actinobacteria, and Fusobacteria were the dominant phyla in both control and treatment samples. Higher doses of prebiotics were found to improve Planctomycetes and Firmicutes while decreasing Proteobacteria and Verrucomicrobia. We observed increasing trends in the abundance of Bacilli, Bacillaceae, and Bacillus bacteria at the class, family, and genus levels, respectively, in a dose-dependent manner. These findings were consistent with the conventional colony count data, which showed a higher prevalence of Bacillus in prebiotic-supplemented groups. Moreover, predicted functional analysis using PICRUSt indicated a dose-dependent upregulation in glycolysis V, superpathway of glycol metabolism and degradation, glucose and xylose degradation, glycolysis II, and sulfoglycolysis pathways. Most of the energy, protein, and amino acid synthesis pathways were upregulated only at lower doses of prebiotic treatment. Our findings suggest that the gut microbiome of O. niloticus can be optimized through nutritional interventions with plant-based polysaccharides for improved growth performance in commercial fish.