Effect of Poultry Excreta and Ground Ear Corn on Growth, Intake, and Digestion of Corn Stover Silage Diets by Yearling Dairy Heifers

Abstract

Four complete diets, 1) 67.5% corn stover: 20.2% ground ear corn: 12.3% fresh poultry excreta (dry matter), 2) 52.7% corn stover:38% ear corn:9.3% poultry excreta, 3) 90% whole corn plant: 10% poultry excreta, and 4) 95.2% whole corn plant:4.8% soybean meal, were stored for 45 days above ground in sealed .02-cm plastic bag silos 2.4m wide×16.8m long. Resulting silages were fed to meet National Research Council recommendations of dry matter intake for .70-kg average daily gain to four groups of seven yearling Holstein heifers for 180 days. Heifers were housed in an open free-stall shed and fed individually via electronic feedgates. Four additional heifers were fed the same diets simultaneously in a 4×4 Latin square digestion trial. Dry matter intakes and average daily gains by the growth trial heifers fed diets in order were 6.3, .40; 5.8, .51; 7.3, .45; and 7.4, .56kg. Dry matter, energy, and crude protein digestibilities for diets in order were 60.4, 61.5, and 45.7; 65.7, 66.3, and 50.8; 68.8, 68.0, and 53.9; and 66.7, 69.2, and 53.7%. While intakes of corn stover diets were lower than whole corn plant diets, average daily gains and digestibility were not different.