The nutrient digestibility of high-protein corn distillers dried grains and the effect of feeding various levels on the performance of laying hens

Currently, corn fractionation technologies are being developed by some ethanol plants in an attempt to improve ethanol yield. Front-end fractionation technology involves separating the endosperm, germ, and bran fractions before fermentation. The endosperm fraction is fermented to produce ethanol and a feed coproduct, which is often called high-protein corn distillers dried grains (HP-cDDG). In general, HP-cDDG from the front-end fractionation process is higher in protein and amino acids but lower in fat and phosphorus than traditional corn distillers dried grains with solubles. In experiment 1, a total of 8 samples were analyzed for TMEn, and a total of 7 samples were analyzed for total and digestible amino acids by the precision-fed conventional rooster assay and cecectomized rooster assay, respectively. The average (and range) TMEn, protein, fat, and fiber values for 8 HP-cDDG samples were 2,851 kcal/kg (2,667 to 3,282 kcal/kg), 44.0 (42.2 to 45.9), 3.03 (1.89 to 5.40), and 7.42% (6.98 to 9.20%; as-fed basis), respectively. The average (and range) total lysine concentration and digestibility coefficient of HP-cDDG were 1.23 (1.13 to 1.38) and 76.1% (67.5 to 85.6%). Experiment 2 was conducted to evaluate the feeding value of HP-cDDG from a plant using front-end fractionation on the performance of laying hens. Five experimental diets were formulated to contain 0, 3, 6, 9, or 12% HP-cDDG. The mash diets were fed to 15 replications of 6 Hy-Line W-36 laying hens per replication from 21 to 41 wk of age. The addition of 3% HP-cDDG significantly improved egg mass as compared with eggs from hens fed the control diet. Overall, at 41 wk no difference in FE, egg yolk color, or specific gravity was attributable to the addition of up to 12% HP-cDDG to the diets as compared with hens fed the control diet. It is important that confirmatory analysis be conducted before using a new fermentation by-product from a new plant or supplier. High-protein corn distillers dried grains is an acceptable feed ingredient when up to 12% is used in a standard laying hen diet during peak production.