Feeding Value of Wet Corn Gluten Feed for Lactating Dairy Cows

Abstract

Twenty Holstein cows just past peak of lactation were arranged in 4×4 Latin squares to evaluate wet corn gluten feed. Each period was 4 wk during which animals were fed for ad libitum consumption of four experimental diets of corn silage, concentrate, and wet corn gluten feed in the following ratios of dry matter: 1) 50:50:0; 2) 50:30:20; 3) 50:20:30; and 4) 50:10:40. Linear decreases of dry matter intake (kg/day) and digestibility (%) were observed when wet corn gluten feed was increased in the diet: 1) 24.0, 74.1; 2) 23.3, 71.5; 3) 22.2, 68.9;and4) 21.5, 69.3. Hemicellulose and ether extract fractions of wet corn gluten feed underwent extensive digestion. Although milk yield (kg/day) was depressed linearly by additions of wet corn gluten feed to the diet: 1) 30.5, 2) 29.9, 3) 28.1, and 4) 28.1, yield of 4% fat-corrected milk remained unchanged: 1) 25.4, 2) 25.2, 3) 24.5, and 4) 24.8 due to increasing milk fat percentage: 1) 2.86, 2) 2.97, 3) 3.15, and 4) 3.21. Milk solids-not-fat percentage and yield and milk protein percentage and yield were depressed linearly by addition of wet corn gluten feed to the diet. Molar percentage of ruminal acetate was increased, whereas propionate decreased when increasing amounts of wet corn gluten feed were fed to the cows. Up to 50 to 60% of the concentrate mixture in corn silage-based rations of lactating dairy cows can be replaced with wet corn gluten feed with little detrimental risk to animal production and health.