The objective of this experiment was to determine if nuclear magnetic resonance (NMR) profiles or blood metabolites could explain dry matter intake (DMI) in developing heifers and/or mature cows in the weeks leading to breeding. A total of 335 heifers and 60 cows were fed a forage-based diet. A general linear model (GLM) was fit for DMI using fixed effects; breed, frame size, birth year. Non-esterified fatty acids (NEFA) had the greatest association with DMI (R2 ranged from 54.4% to 58.1% and 64.4% to 70.6%) in heifers and cows, respectively. The NMR profiles accounted for the smallest amount of variation (51.9% and 55.6%) for rumen metabolism and (52.0% and 55.8%) for cellular metabolism in heifers and cows, respectively. Additional exploration of how to profile NMR data is needed. The models containing NEFA accounted for high levels of variation, where fit plots indicated these predictions could be used to manage animals in distinct groups for DMI.