|Torbert, Henry - Allen|
Submitted to: Animal Feed Science And Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/18/2001
Publication Date: 8/18/2001
Citation: Moss, B.R., D.W. Reeves, J.C. Lin, H.A. Torbert, P. Mask, and W. Kezar. 2001. Yield and quality of three corn hybrids as affected by broiler litter fertilization and crop maturity. Anim. Feed Sci. and Technol. 94:43-56. Interpretive Summary: Corn silage has a high nutrient demand and could be used as an effective sink for environmentally safe disposal of poultry litter, but the impact of litter on silage quality has not been determined. We compared poultry litter to commercial fertilizer as a nitrogen source for three corn hybrids representative of those used for silage in the southeastern USA. We evaluated silage quality (crude protein (CP), acid-detergent fiber (ADF), and in-vitro dry matter disappearance (IVDMD)] of the three hybrids; harvested at three different maturities. About 37% of the litter nitrogen was plant available the year applied, at the application rate that resulted in maximum silage yield (6 to 8 tons/acre). At these litter rates, nutritional values of silage were equivalent to silage grown with recommended rates of commercial nitrogen fertilizer (180 lb nitrogen/acre as ammonium nitrate) for irrigated production. This research demonstrates that litter can provide corn silage yields and nutritional values comparable to commercial nitrogen fertilizer. The information can be used in nutrient management plans by specialists from Cooperative Extension, USDA-NRCS, and crop consultants, wherever poultry litter is available and silage is produced.
Technical Abstract: Hybrid choice, organic N and ensiling maturity may impact yields and nutrient quality of corn silage. Three corn hybrids (Zea mays L.) (Pioneer 3136, 3140, 3154) with five N fertilization treatments were planted for 2 years and harvested at 1/3, 2/3 or full milk line in a split-split plot design in east central Alabama. Nitrogen treatments were: 0, or 4.5, 9.0, 13.5 or 18.0 Mg/ha broiler litter and a control of 202 kg N/ha as NH4NO3. At harvest, milk line and whole plant, stover and grain yields were determined and subjected to forage quality analyses. Whole plant yields were greatest for the 13.5/18.0 litter treatments with no difference between 9.0 Mg/ha and NH4NO3. Nutrient content varied with N source and year. During a dry year, NH4NO3 had greater crude protein and lower ADF values, but the 13.0/18.0 Mg/ha litter rates had this ranking in a wetter year. Whole plant IVDMD values were greater for NH4NO3 than the 13.5/18.0 litter treatments during both years, but this occurred only during the dry year for stover. Hybrid did not consistently affect yield, but Hybrid 3136 had greater nutrient values in several evaluations. Increased maturity increased grain and whole plant yield, but effects on nutrient quality were variable. Results indicate that high applications of broiler litter provide comparable yields to commercial fertilizer without an adverse effect on nutrient quality, except digestibility may be compromised.