Feeding wet distillers grains at all levels improved feed conversion compared to cattle fed the control diet. The average net energy for gain value for wet distillers grains was 1.5 times the energy value of corn. Economic returns declined slightly as the percentage of wet distillers grains increased in the diet, but remained above the two diets without distillers grains, he added. The price charged by the ethanol plant used in the study was a third of the price of corn purchased. Transportation costs are critical, he said, adding that finishing operations should be located within 20 miles of an ethanol plant.
Many ethanol plants use income from selling distillers grains to increase returns to the plant.
Trenkle said some plants dry distillers grains to transport them long distances to dairy cattle areas for feed. The problem with drying, he said, is that it results in a loss of feed value from solubles removed with the liquid. Researchers are unclear about the reason for the loss, but there is less energy in the dry distillers grains, resulting in a less valuable feed for finishing cattle.