Fig. 5

Significant associations between microbial clades and sample metadata. a Heatmap summarizing all the significant associations between microbial clades and sample metadata. Color key: -log(q-value) * sign (coefficient). Cells that denote significant associations are colored (red or blue) and overlaid with a plus (+) or minus (−) sign that indicates the direction of association: Diet (+), higher abundance in salmon fed the IM diet; Sample_origin (+), higher abundance in mucosa samples; Histology_LPC (+), higher abundance in salmon scored abnormal regarding lamina propria cellularity (LPC) in the distal intestine; DISI (+), positive correlation between microbial clade abundance and distal intestine somatic index (DISI); qPCR_immune_response (+) / qPCR_barrier_function (+), negative correlation between microbial clade abundance and the gene expression levels. b Taxa that are more abundant in the intestinal mucosa than the digesta. c Representative taxa showing increased relative abundances in both intestinal digesta and mucosa of salmon fed the IM diet. d The positive correlation between the relative abundance of Brevinema andersonii and immune gene expression levels in the distal intestine. Note that the expression levels of the immune genes decreased as the PC1 of the PCA increased. e The negative correlation between the relative abundance of the Spirochaetaceae and the expression levels of barrier function relevant genes. Also note that the expression levels of the barrier function relevant genes decreased as the PC1 of the PCA increased. p__, phylum; o__, order; f__, family; FDR, false discovery rate; N.not.zero, number of observations that are not zero; REF, reference diet; IM, insect meal diet