Early life events are key for the development of healthy and productive poultry particularly with broiler birds. The starter phase is a key stage in the production cycle. Early nutrition is creating an opportunity for modern broiler industry to further advance and improve the overall performance, health status and welfare of commercial fast and slow growing broiler chickens, as well as further reduce antimicrobial usage. The general goal of this project is to develop scientifically validated protocols for the optimal implementation of early feeding in on-farm hatching systems and as well in conventional hatching systems in the hatchery. The goal is to optimize protocols for both fast growing and slow growing broiler chickens breeds. These protocols will be established based on the impact on animal-based indicators for animal production, welfare, gut health, nutrient metabolism, immune system, occurrence of production diseases and antimicrobial usage, linked with the economic impact and social added value.