Fig. 1

Overview of the experimental design and diversity of microbial community among different groups. a Overall workflow of sample collection from piglets, and sows at each sampling time point. All sows and their piglets were co-raised in the same environment. All swab samples were used for 16S rRNA gene sequencing, and a subset of samples was randomly selected for metagenomic sequencing. b The Chao1 index. c The Shannon index. Each point represents one sample as indicated by the axis label and color of the point. Letters (a, b, c, d) above the boxplots indicate significant differences between the two groups (P < 0.05). d Non-metric Multidimensional Scaling (NMDS) plot according sample group based on the abundance of ASVs. The plot is based on the Bray–Curtis distances between pairs of samples. Each point represents one sample; ellipses represent the 95% confidence for all points within each cluster. Stress, the value used to estimate the NMDS ordination fitness. R, the statistic from the analysis of similarities (ANOSIM) that compares the mean of ranked dissimilarities between groups to the mean of ranked dissimilarities within groups. P, the P-value from ANOSIM analysis between groups