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MEANS OF IMPROVING THE PERFORMANCE OF RUMINANTS FED CORN RESIDUES
Abstract
As the level of corn (0, 25, 50, 75, 100%) in a corn stover diet increased, there was a curvilinear increase in dry matter digestibility (DMD) and dry matter intake (DMI). Neutral detergent fiber (NDF) digestibility showed a curvilinear and a cubic decrease as level of corn in the diet increased. Both particulate and fluid rates of passage were decreased on the 100% corn diet. Rumen pH declined with increasing level of corn. When corn was fed at restricted levels the DMD and NDF digestibility showed linear increases, indicating that associative effects may be larger than previously thought. Cattle were fed the same total amounts of grain and stalklage, those fed a synthetic corn silage and then a finishing diet had larger intakes, higher daily gains and better feed efficiency than cattle fed stalklage and then a finishing diet. There were no differences in carcass data. Form of soyhull (whole toasted, ground toasted or whole untoasted) did not affect rate of NDF digestion (6 to 7%/hr) or rate of protein digestion (4%/hr). Rate of passage of whole (2.79%/hr) was slower than ground soyhulls (4.52%). In vitro dry matter disappearance (IVDMD) was lower for soyhulls (78%) than for corn (94%). Pelleting soyhulls solubilized hemicellulose and increased IVDMD to 86%. In a lamb trial the energy sources and DMD were: corn, 63.6; whole soyhulls, 61.6; ground soyhulls, 59.9; pelleted whole soyhulls, 59.2. Corn and pelleted soyhull diets showed the largest negative associative effects. In a steer digestion trial whole soyhulls or corn were fed at 0, 12.5, 25 or 50% of the diet. DMD increased and rate of NDF digestion and rumen pH at 12 hr postfeeding both declined with increasing level of energy in the diet. Shape of the pH curve was different for corn and soyhull diets. Rate of particulate passage (3.1%/hr) and fluid flow (7.7%/hr) were not changed by additions of corn or soyhulls. Seven corn varieties were planted in 1979 and 9 varieties in 1980, in both irrigated and non-irrigated plots. Population densities for non-irrigated were low (44,300 plants/ha) and medium (53,100 plants/ha). The irrigated plots had the low and medium plus a high population density (64,200 plants/ha). Grain yield was affected by variety, population density, irrigation and year. . . . (Author's abstract exceeds stipulated maximum length. Discontinued here with permission of author.) UMI
Subject Area
Livestock
Recommended Citation
MCDONNELL, MICHAEL LLOYD, "MEANS OF IMPROVING THE PERFORMANCE OF RUMINANTS FED CORN RESIDUES" (1982). ETD collection for University of Nebraska-Lincoln. AAI8228153.
https://digitalcommons.unl.edu/dissertations/AAI8228153