Estimating feed intake of dairy heifers: A quick discussion
Estimating feed intake (dry matter intake) of dairy heifers is an important part of dairy heifer nutrition, but there is a little catch and a trick to get it close.
Many of us use heifer bodyweight to estimate feed intake of dairy heifers. Bodyweight-based heifer feed intake equations “sort of” work, but often dairy heifer feed intake is greater or less than predicted. So what’s the catch?
The catch: Dairy heifer feed intake is also very sensitive to the amount of NDF in the diet. For example when a low NDF (40 percent), high-quality forage-based diet is fed to bred heifers, feed intake will be greater than desired, perhaps causing over-conditioning.
The trick: Use NDF intake for formulating dairy heifer diets and estimating dry matter (feed) intake. NDF intake as a percentage of bodyweight is nearly a constant 1.0 percent of bodyweight in dairy heifers. Thus, at a given heifer bodyweight, feeding the proper or desired amount of NDF to a dairy heifer is what is controlling her daily feed intake.
The chart below defines dietary NDF, NDF intakes and dry matter intakes for Holstein heifers based on bodyweight.
About the author: Pat Hoffman is a Vita Plus dairy technical support specialist. He received professor emeritus status after completing a 35-year career with the University of Wisconsin-Madison Department of Dairy Science. Based at the Marshfield ag research Station, Hoffman’s UW-Extension services included application of dairy research and the development of dairy outreach education programs. His research focused on development of dairy replacement heifers. Hoffman earned his bachelor’s degree from UW-Platteville and his master’s in dairy science from UW-Madison. He is a member of the American Dairy Science Association and previously served as president of the Midwest Branch.
Calf and heifer nutrition