Fig. 4

The difference in microbial production of tryptophan metabolites between healthy and diarrheal weaned piglets and correlations between tryptophan metabolites and diarrhea-related indicators. a–f The concentration of IAld, 2-indolecarboxylic acid, 3-indolebutyric acid, indole-3-carboxylic acid, indole-3-methyl acetate, and 3-indolepropionic acid in the feces of piglets. g The correlation analysis between the six tryptophan catabolites and diarrhea-related indicators. Data are expressed as the mean ± SEM (n = 10). *P < 0.05