Effects of Dietary Fiber and Reduced Crude Protein on Ammonia Emission from Laying-Hen Manure

Abstract

Ammonia (NH(3)) emission is a major concern for the poultry industry. The objective of this research was to determine whether inclusion of dietary fiber and a reduced dietary CP content would decrease NH(3) emission from laying-hen manure. A total of 256 Hy-Line W-36 hens were fed diets with 2 levels of CP (normal and reduced) and 4 fiber treatments in a 2 x 4 factorial arrangement. The fiber treatments included a corn and soybean meal-based control diet and diets formulated with either 10.0% corn dried distillers grains with solubles (DDGS), 7.3% wheat middlings (WM), or 4.8% soybean hulls (SH) to contribute equal amounts of additional neutral detergent fiber. The CP contents of the reduced-CP diets were approximately 1 percentage unit lower than those of the normal-CP diets. All diets were formulated on the basis of digestible amino acid content and were formulated to be isoenergetic. Fresh manure was collected such that pH, uric acid, and Kjeldahl N contents could be measured. The NH(3) emission from manure was measured over 7 d by placing pooled 24-h manure samples in NH(3) emission vessels. Data were analyzed by ANOVA with Dunnett's multiple-comparisons procedure to compare results from the fiber treatments with the control, whereas the main effect of protein was used to compare the normal- and reduced-CP treatments. Dietary corn DDGS, WM, or SH lowered (P <or= 0.01) the 7-d cumulative manure NH(3) emission from 3.9 g/kg of DM manure for the control to 1.9, 2.1, and 2.3 g/kg of DM manure, respectively, and lowered (P < 0.05) the daily NH(3) emission rate. Results of this study showed that dietary inclusion of 10.0% corn DDGS, 7.3% WM, or 4.8% SH lowered NH(3) emission from laying-hen manure; however, reducing the CP content by 1 percentage unit had no measurable effect on NH(3) emission.

Modeling of Dynamic Ammonia Concentrations in Two Commercial Layer Hen Houses

“…The relationship between birds' diet and excreted nitrogen contents has been widely studied. While Summers et al (1993) and Roberts et al (2007) successfully reduced the amount of excreted nitrogen by diet manipulations, claimed no significant effects of crude protein percentage in diet on the amount of total N and uric acid-N in fresh litter of layer hens. Manure removal strategy determined both the amount and the surface area of manure remaining in the pit.…”

Effects of dietary corn distiller's dried grains with solubles on ammonia emission, production performance, manure characteristics, and economic efficiency for laying hens

“…Dietary fiber has been shown to cause a decrease in manure pH and decrease uric acid-N excretion with a concurrent decrease in NH 3 emissions. Roberts et al (2007a) fed laying hens diets that contained 10.0% corn distiller's dried grains with solubles, 7.3% wheat middlings, or 4.8% soybean hulls. The NH 3 emission from the laying-hen manure was decreased 41%, 38%, and 27% for the corn distiller's dried grains with solubles, wheat middlings, and soybean hulls, respectively (Roberts et al, 2007a).…”

“…Roberts et al (2007a) fed laying hens diets that contained 10.0% corn distiller's dried grains with solubles, 7.3% wheat middlings, or 4.8% soybean hulls. The NH 3 emission from the laying-hen manure was decreased 41%, 38%, and 27% for the corn distiller's dried grains with solubles, wheat middlings, and soybean hulls, respectively (Roberts et al, 2007a). No repartitioning of N excretion could be detected in the study but manure pH was decreased from 7.08 for the control-fed hens to 6.77, 6.80, and 6.85, respectively, for the hens fed corn distiller's dried grains with solubles, wheat middlings, and soybean hulls (Roberts et al, 2007a).…”

Evaluation and application of a dynamic emissions chamber for quantifying gaseous emissions from laying hen manure

“…On-site filter efficiency is summarized in Chapter 3. Roberts et al, 2007;Wu-Haan et al, 2007;, Roberts et al, 2009. Amino acids supplied above the level of the limiting amino acid cannot be used and the nitrogen is excreted.…”

“…Also, the higher supply of DDGS in animal diets, because of the rapid increase in production of ethanol encourages comparison (Waldroup et al, 2007). Roberts et al (2007) found a reduction of approximately 40% in NH 3 emission from manure of laying hens fed 10% dietary DDGS. In spite of the MAEMU"s precision and real-time measurement capabilities, its relative immobility and high cost limits the widespread use for baseline emission and mitigation studies.…”