Impact of Cow Size on Nutrient Needs
Nutrient needs for cows of different body weights are not the same. Cows that weigh 1,300 pounds have a greater nutrient (pounds of protein, pounds of energy (TDN), ounces of mineral, etc) requirement compared to cows that weigh 1,000 pounds. If a 1,000 pound cow and a 1,300 pound cow are grazing the same forage resource, the 1,300 pound cow will need to consume more of that forage to meet her requirements. Maintenance feed intake is proportional to metabolic body weight which is described as body weight to the 3/4 power (body wt.3/4).