We do not recommend feeding forage prior to weaning because the nutrient content is not high enough for optimal growth. Once the calf is weaned and eating 4 to 5 pounds of a calf starter containing fiber (such as oats or barley), then offer forage to the calf.
The end product of microbial digestion of forages is primarily acetic acid. The microbial end product of grain (starch) is propionic and butyric acids. Butyric acid is the one VFA (Volatile Fatty Acid) that directly supplies the rumen wall with energy. Therefore grain should only be fed before the rumen is well developed. Then they can better digest forages.
Mike Hutjens, Extension Dairy Specialist, University of Illinois - Illiini DairyNET
Arlyn Heinrichs, Dairy Extension, Penn State University.
