Research
| Title： | Exploring the indicator gut microbiota taxa in grass carp (Ctenopharyngodon idella): Correlations with growth rates |
|---|---|
| First author： | Zhang, Zhimin; Chen, Wen; Xu, Tingting; Liu, Haokun; Jin, Junyan; Yang, Yunxia; Zhu, Xiaoming; Han, Dong; Xie, Shouqi |
| Journal： | AQUACULTURE |
| Years： | 2025 |
| DOI： | 10.1016/j.aquaculture.2024.742080 |
| Abstract： | The gut microbiota is important for fish nutrition and growth, and individual variations in growth can adversely affect fish production and aquaculture practices. To explore potential correlations between the gut microbiota and fish growth performance, this study aimed to analyze the gut microbiota of grass carp at different growth rates using two extruded diets. The results revealed that the gut microbial community structure was significantly related to the growth rate (P = 0.001). Compared to fast-growing grass carp, slow-growing individuals exhibited greater alpha diversity but lower abundances of the core gut microbiota. The dominant phyla in the gut were Proteobacteria (54.6 %) and Firmicutes (21.2 %), followed by Actinobacteria (6.3 %) and Bacteroidetes (5.9 %), with fast-growing grass carp harbouring higher abundances of Firmicutes (32.3 % vs. 13.3 %) and Bacteroidetes (7.5 % vs. 4.7 %) than slow-growing grass carp. However, compared with those in the corresponding slowgrowing groups, the Firmicutes to Bacteroidetes (F/B) ratios in the fast-growing groups did not consistently increase. In addition, the analysis through linear discriminant analysis effect size (LEfSe) identified numerous gut microbiota indicator taxa between the two groups. The fast-growing grass carp presented a greater presence of cellulose, amylose-degrading, and health-associated bacteria, such as Erysipelatoclostridium (8.6 % vs. 1.6 %), Leptotrichia (1.5 % vs. 0.3 %), and Anaerorhabdus furcosa group (0.6 % vs. 0.01 %). In contrast, the slow-growing grass carp had more opportunistic pathogenic bacteria such as Ralstonia (0.7 % vs. 0.03 %), Brevundimonas (9.6 % vs. 2.6 %), and Pandoraea (8.8 % vs. 2.0 %). Furthermore, functional potential analysis of the gut microbiota revealed significantly greater proportions of carbohydrate metabolic gene pathways in the fast-growing groups and more abundant infectious disease gene pathways in the slow-growing groups. These results suggest that the favourable gut microbiota observed in grass carp may contribute to their accelerated growth. This study highlights the substantial associations of the gut microbiota with the growth rates of grass carp and the challenges of using the F/B ratio as a biomarker for growth traits in aquaculture. These findings provide new insights into the screening of beneficial microbes/potential probiotics to promote fish growth and enhance aquaculture production. |
