In response to sustainability and ethical pressures, the poultry industry continually explores strategies to enhance animal performance, health, and welfare while reducing feed costs and environmental impact from nutrient excretion. One promising approach is the adoption of low crude protein (CP) diets. When properly balanced with indispensable amino acids to meet hen requirements, these diets can reduce operation costs, given that protein occupies the second-highest feed input cost. Environmentally, lowering dietary protein reduces nitrogen excretion and may also improve gut health by limiting undigested protein reaching the hindgut, reducing undesirable fermentation. Dietary CP and amino acid levels are regularly optimized by breeding companies; however, limited data exist on whether these revised specifications can be reduced without compromising performance. We, therefore, investigated laying hen responses to graded reductions in balanced dietary CP. The results confirmed that balanced dietary protein reduction maintained performance and most egg quality traits while lowering nitrogen excreted and feed costs. Marginal influences on mineral (improved eggshell but lowered tibia breaking strength) and lipid (higher abdominal fat) metabolism were also observed. Given current breeding targets of extended laying, the long-term effects of balanced protein reduction warrant further investigation, particularly on performance, mineral metabolism, eggshell quality, and bone health.

Read the full article in the Journal of Animal Science.