Metabolomic and proteomic characterisation of intestinal responses to Chlorella vulgaris and CAZyme supplementation in weaned piglets

This study investigated intestinal adaptations to dietary supplementation with Chlorella vulgaris and CAZyme in weaned piglets, using complementary metabolomic and proteomic profiling. Forty-four piglets were assigned to four diets for 15 days: a control diet; 5% C. vulgaris (CH); CH supplemented with 0.005% Rovabio® Excel AP (CH + R); and CH supplemented with 0.01% of a four-CAZyme mixture (CH + M). Metabolomics was performed on intestinal tissue and faecal samples from all groups, while proteomics was conducted on intestinal tissue from the Control, CH, and CH + M groups. Global metabolic fingerprints showed a high degree of similarity among treatments. Proteomics identified 5146 proteins, with differential abundance restricted to the CH + M versus Control comparison. Proteins down-regulated in CH + M were primarily associated with translation, chromatin structure, and RNA binding. By interpreting metabolomic and proteomic outcomes, this study provides a comprehensive biological perspective on how piglets adapt to microalgae-based diets, even under subtle metabolic shifts. These integrative findings build upon previous physiological and microbiota observations and contribute to a deeper understanding of the molecular responses induced by sustainable functional feed ingredients in monogastric nutrition.