Based on requirements generated by the computer program that accompanies Nutrient Requirements of Dairy Cattle, 2001, National Academy of Sciences, National Academy Press, Washington, DC. The crude protein requirements of animals <150 kg are relatively high and could be reduced by the use of protein sources with higher RUP proportions. DMI, dry matter intake; RUP, rumen undegradable protein; RDP, rumen degradable protein; ME, metabolizable energy.