Preliminary study on the effects of different dietary spermine levels on intestinal function, microflora, and metabolism in weaned Wuzhishan piglets

Abstract

Background Spermine has been shown to promote intestinal maturation and protect intestinal health. However, its potential as a dietary feed additive for improving intestinal health in Wuzhishan piglets remains unclear. In this study, eighteen weaned Wuzhishan piglets were randomly assigned to three groups (n = 6 per group) and provided with either a basal diet (control), a diet supplemented with 0.01% spermine, or a diet supplemented with 0.03% spermine for 28 days. Results Dietary supplementation with 0.01% spermine significantly improved growth performance (p < 0.05) and increased small intestinal α-amylase and trypsin activities (p < 0.05). It also significantly upregulated anti-inflammatory cytokines and downregulated pro-inflammatory cytokines in small intestine (p < 0.05). Compared with the control group, the relative abundance of the beneficial gut bacterium Prevotella was significantly increased in the 0.01% spermine group, while that of the harmful bacterium Streptococcus was significantly decreased in both the 0.01 and 0.03% spermine groups (p < 0.05). Additionally, DNA synthesis-related metabolic capacity and immune-related metabolite levels were significantly elevated in both the 0.01 and 0.03% spermine groups (p < 0.05). Conclusion These findings suggest that dietary supplementation with 0.01% spermine can effectively alleviate weaning-induced intestinal dysfunction in Wuzhishan piglets by improving intestinal morphology, digestive enzyme activity, and immune responses, modulating the relative abundance of specific gut bacteria, and enhancing metabolic capacity.