This study, conducted as part of the mEATquality European Union project, examined the main effects and interactions of space allowance and dietary fibre provision in higher-welfare systems. Using the slower-growing genotype, Hubbard JA757, we assessed broiler performance, intrinsic meat quality and the molecular mechanisms underlying these outcomes. These findings highlight how husbandry factors interact to shape meat phenotypes, offering a molecular framework to support quality-focused, welfare-aligned, and environmentally conscious meat production.