Rice flowering improves the muscle nutrient, intestinal microbiota diversity, and liver metabolism profiles of tilapia (Oreochromis niloticus) in rice-fish symbiosis

Abstract

Background Rice-fish symbiosis, as an ecological and green aquaculture model, is an effective measure to relieve the environmental stress from intensive aquaculture. Compared with traditional aquaculture, the altered rearing pattern and environment will make differences in muscle nutrient and quality, intestinal microbiota, body metabolism, and even disease resistance in fish. Results To investigate this, we explored the differences between rice-tilapia (aRT and bRT) and tank-tilapia (aTT and bTT) models at the periods before and after rice flowering using 16S rRNA sequencing and untargeted metabolomics. The results showed that compared with tilapia reared in the tank model, the fish body length and weight, the muscle total umami amino acid, and monounsaturated fatty acid content were obviously higher in the rice-fish model, especially after rice flowering. Compared with other groups, the intestinal microbiota diversity of fish in the bRT group was significantly higher; the dominant microbiota was Bacteroidetes and Firmicutes at the phylum level, Bacteroides and Turicibacter at the genus level, and the relative abundances of Gram-negative, potentially pathogenic, and stress-tolerant bacteria were the highest, lowest, and highest, respectively. Besides, the differential metabolite analysis indicated that rice-fish symbiosis improved the metabolic profiles and modulated the metabolic pathways in tilapia. Moreover, the correlation analysis of 16S sequencing and metabolomics showed that Bacteroides showed a positive correlation with many metabolites related to amino acid, fatty acid, and lipid metabolism. Conclusions In summary, rice flowering improves the tilapia muscle nutrient, intestinal microbiota diversity, and disease resistance and modulates the host metabolism to acclimatize the comprehensive environment in rice-fish symbiosis. Specifically, rice flowering alters the microbiota abundance involved in amino acid, fatty acid, and lipid metabolism, resulting in improving the muscle nutrient and quality through the crosstalk of gut microbial and host metabolism. Our study will provide not only new insight into the gut microbiota-metabolism-phenotype axis, but also strong support for the promotion and application of rice-fish symbiosis in aquaculture.

Rice-fish symbiosis improves the muscle nutrition and intestinal flora diversity of tilapia

“…Combined with the result of beta diversity analysis, the intestinal flora diversity of tilapia in the R group was higher than that in the T group, which is consistent with the previous report. 18 Further analysis of the intestinal flora composition of tilapia showed that the dominant groups of intestinal flora in the two groups were Proteobacteria, Planctomycetes, Firmicutes, Fusobacteria, Actinobacteria, Cyanobacteria, and Bacteroidetes, which is consistent with the results of previous studies. 18 In previous studies, Pseudomonas was reported to have beneficial functions such as improving plant nutrition, degrading toxic substances, producing antibiotics, and inducing systemic resistance.…”

“…Meanwhile, the growth cycle of tilapia is almost the same as that of rice, and tilapia is also a suitable farmed fish for rice-fish symbiosis. 18 In this study, we analyzed the composition of amino acids and fatty acids in the tilapia muscle from ricefish symbiosis and pond culture. We explored the structure Brevundimonas plays a positive role as beneficial gut bacteria in enhancing intestinal immunity and maintaining gut health in fish.…”

Heat-Killed Saccharomyces boulardii Alleviates Dextran Sulfate Sodium-Induced Ulcerative Colitis by Restoring the Intestinal Barrier, Reducing Inflammation, and Modulating the Gut Microbiota

“…Previous studies have shown that interventions with beneficial substances can reshape the gut microbiota in colitis mice, leading to significant changes in certain bacterial genera [ 37 , 38 ]. In our study, we observed that compared to DSS-induced model mice, treatment with heat-killed S. boulardii increased the abundance of beneficial bacterial genera, including Dubosiella [ 39 ], Ligilactobacillus [ 40 , 41 ], Turicibacter [ 42 , 43 ], and Ileibacterium [ 44 ]. The growths of these genera were significantly suppressed in DSS model mice, indicating that heat-killed S. boulardii intervention can regulate the gut microbiota by restoring the abundance of dominant bacteria, thus achieving a new balance.…”

Multi-Omics Analysis to Understand the Effects of Dietary Proanthocyanidins on Antioxidant Capacity, Muscle Nutrients, Lipid Metabolism, and Intestinal Microbiota in Cyprinus carpio

“…In animal intestines, the Firmicutes and Bacteroidetes phyla are dominant and play essential roles in promoting host health, boosting immunity, and maintaining homeostasis [80]. An elevated ratio of F/B is linked with some metabolic syndrome, such as obesity and chronic inflammation [81].…”