To evaluate the effect of rates of distillers’ grain supplementation on substitution for pasture, IowaStateUniversity researchers conducted two stocker-grazing studies at the ISU McNay Research Farm near Chariton, Iowa. In the first year, three groups of growing heifers were compared. They were grazed for 136 days and supplemented with 0, 0.5 or 1.1 percent of their bodyweight with DDG. Stocking rates were in­creased 22 percent and 44 percent for the two respective supplemented treat­ments. Estimates of pasture consumption, based on sward height measurements, suggested no difference between the control and the group supplemented at the lower rate. The cattle fed the highest rate of DDG supplementa­tion appeared to consume less grass per head as shown in the reduction of pasture sward height. Cattle on the three treatments gained 223, 304 and 830 pounds per acre. This increased productivity was due to a combination of an increased rate of gain for supplemented cattle and also the stocking rate. The cattle were fed a 100 percent-pelleted DDG pellet for the first half of the study, then switched to typical DDG meal fed in bunks for the remainder of the study. Bunk feeding appeared to control the waste but increased the labor required when rotating pastures.

 In the second stocker study at the McNay Farm, unsupplemented heifers were compared to those supplemented with 1.5 percent of their bodyweight of Dakota Bran. Dakota Bran is a co-product produced by a fractionation process where the corn germ is separated, and oil is partially removed prior to fermentation. The corn bran is also removed at that time and the remaining endosperm fraction is used for ethanol fermentation. Dakota Bran is a combination of corn bran and condensed distillers’ soluble. This feedstuff can be more easily pelleted, making it an attractive grazing supplement from a handling perspective. During the supplementation period, cattle fed the Dakota Bran gained 1.48 pounds per day compared with 0.79 pounds per day for the control cattle. Calculations based off sward height measurements indicated that the supplemented cattle consumed 26.8 percent less pasture. Gain per acre increased by approximately 100 pounds and at a similar cost, based on the costs at the time of the study.

For a multi-page fact sheet on using ethanol co-products as supplements in grazing programs, including a summary of these trials, click here.