The nutritional adequacy of livestock feed directly affects animal health, immune function, and welfare — feed formulation decisions have welfare consequences that extend beyond mere growth performance.
Livestock feed formulation decisions carry welfare consequences that extend far beyond growth performance and are often invisible at farm level. Ruminants fed high-grain feedlot diets develop subacute ruminal acidosis at rates that represent a significant welfare burden — the condition causes chronic discomfort, liver abscesses, and immune dysregulation. Broiler feed regimes that maximize growth rate produce birds whose cardiovascular and musculoskeletal systems cannot keep pace — heart failure and leg problems resulting from metabolic mismatch between rapid growth and system capacity. Nutrition also affects behavior: tryptophan-adequate sow diets produce calmer animals with better piglet survival rates. The welfare implications of nutrition are an underappreciated lever for improvement that requires collaboration between nutritionists, veterinarians, and welfare scientists.