A review of resistant starch as a functional fibre in poultry: microbial fermentation and short-chain fatty acid interaction–mediated effects on gut and bone health

1. This review discusses the functional role of resistant starch (RS) in poultry. It was hypothesised that RS–microbiota interactions and microbial fermentation-derived short-chain fatty acids (SCFA) mediate improvements in nutrient digestion, immune modulation, gut and bone integrity.2. The fermentation of RS in the distal gastrointestinal tract produces microbial metabolites such as short-chain fatty acids (SCFA) which selectively modulate gut microbial community. Individual SCFA are linked with different bacteria groups and taxa. The bacteria, in turn, may increase the production of SCFA. Different RS and concentrations in diets may yield variable quantities and profiles of SCFA under distinct physiological conditions and in different animal species.3. These SCFA regulate cytokine production via activation of G protein-coupled receptors (GPRs), GPR43(FFAR2) and GPR41 (FFAR3) and/or inhibiting histone deacetylase (HDAC) in immune and mononuclear cells. These play crucial roles in modulating the immune system, gut health and bone health.4. Overall, RS–microbiota interactions and SCFA production provide a mechanistic basis for improving intestinal and skeletal health in poultry, particularly under inflammatory challenges.