Producers should not feed hay to calves less than 12 weeks of age, and there are several good reasons why.

  • Hay is bulky and high in fiber and thus fills the gut with lower nutrient available feed sources, such as milk and starter.  Calves need these nutrients for healthy growth.
  • The first 6 months of a calf’s life are the most rapid and critical growth stages of its life.  Highly available sources of protein and energy are more important than can be digested through fiber-rich diets of hay and grass.
  • A calf’s rumen develops over the first 6 months of age, and it typically takes this long for healthy rumen papillae to develop for maximum nutrient absorption.