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

Abstract

Rice-fish symbiosis is an ecological farming model that can improve fish's muscle nutrient profile and intestinal flora. We investigated the effect of rice-fish symbiosis on tilapia's intestinal flora and muscle nutrients. We used 16S rDNA technology to analyze the intestinal flora of tilapia in pond culture and rice-fish symbiosis. Furthermore, spearman correlation analysis was performed on tilapia intestinal flora and muscle nutrients. The results showed that the contents of Valine, Phenylalanine, and Docosahexaenoic acid were significantly higher in the rice-fish symbiosis than those in the pond culture (p<0.05). Intestinal flora analysis showed that the diversity in rice-fish symbiosis was significantly higher than in pond culture (p<0.05). Meanwhile, the abundance of Brevundimonas, Pseudomonas, and Ralstonia in rice-fish symbiosis was significantly higher than those in pond culture (p<0.05), but Pirellulaceae unclassified and Cyanobium_PCC-6307 were opposite. The number of 8 predictive functional tilapia genes in the rice-fish symbiosis was higher than in the pond culture. Correlation analysis showed that the abundance of Ralstonia was positively correlated with the contents of Valine, Phenylalanine, and Docosahexaenoic acid, respectively. Our study shows that the rice-fish symbiosis could improve muscle nutrient profile and intestinal flora diversity in tilapia. This study will help to improve the rice-fish symbiosis model and provide a scientific basis for ecological aquaculture and healthy fish production.