Intake and growth of prepubertal dairy heifers fed reduced-fat dried distillers grains

Recent growth in the ethanol industry has led to increased availability of distillers grains that have undergone various processing methods resulting in differing nutrient composition. A modified dried distillers grains product with reduced fat due to removing oil through a solvent extraction process provides a new feed option for dairy heifers. The objective of this study was to evaluate intake, feed efficiency, and growth of dairy heifers fed diets containing reduced-fat dried distillers grains with solubles (RFDGS). Holstein heifers (n = 27), averaging 161 ± 9 d of age and 157.5 ± 11.4 kg at the start of the study, were blocked according to BW and fed 1 of 3 dietary treatments. Dietary treatments included control, dried distillers grains fed at 20% of the diet DM, and RFDGS fed at 20% of the diet DM for 12 wk. Heifers were weighed every 2 wk to determine ADG. Hip and withers heights were measured on d 0, 42, and 84 of the study, and BCS were determined on d 0 and 84. Blood samples were collected via coccygeal venipuncture at the end of the study for determination of plasma urea nitrogen. In situ DM disappearance and intestinal CP disappearance were determined for feed and diet samples using lactating cows. Dry matter intake, BW gain, and feed efficiency were similar among treatments. In summary, inclusion of either DDGS or RFDGS at 20% of the diet resulted in similar intake, feed efficiency, and gains, and they are viable options for replacement dairy heifers.