The Effect of Zinc Gluconate Supplementation on the Intestinal Microbiota and Growth Performance of Yorkshire Pigs

The gut microbiota significantly influences the healthy growth and development of animals. However, the alterations in the gut microbiota of Yorkshire Pigs mediated by specific trace elements, such as zinc gluconate, and their associations with growth phenotypes remain to be elucidated. This study aimed to investigate the effects of dietary zinc gluconate supplementation on the gut microecology of Yorkshire Pigs. Twenty Yorkshire Pigs were randomly divided into a control group (NC) and a treatment group (GZn, fed a diet containing 0.1% zinc gluconate) for 52 days. The diversity, composition, and potential functions of fecal microbiota were evaluated via 16S rRNA gene sequencing. The results showed that dietary zinc gluconate supplementation altered the gut microbiota of Yorkshire pigs, evidenced by distinct community clustering in beta diversity and increased alpha diversity (species richness and diversity). In terms of the composition of taxonomic units, a significant beneficial succession occurred among the core bacterial genera: potential probiotic genera (such as Clostridia_UCG-014) that were significantly enriched, while genera associated with negative correlations with growth traits or potentially pathogenic (such as Streptococcus and Escherichia-Shigella) were effectively suppressed. Although Firmicutes and Bacteroidota remained the shared dominant phyla, the abundance of core genera underwent a significant succession. Spearman correlation analysis revealed that potential probiotic genera positively correlated with body weight and body length (such as Clostridia_UCG-014, Methanobrevibacter, and Oscillospira) were significantly enriched in the GZn group; conversely, genera negatively correlated with growth traits (such as Streptococcus and Escherichia-Shigella) were enriched in the NC group. Furthermore, KEGG pathway functional prediction indicated that the gut microbiota of the GZn group was predicted to be enriched in fundamental metabolic functions such as amino acid metabolism and energy metabolism. In conclusion, dietary zinc gluconate supplementation can effectively improve the growth phenotypes of Yorkshire Pigs, and this improvement is associated with shifts in the gut microecological structure and predicted microbial metabolic functions.