Reducing Ammonia Emissions from Poultry Litter with a New Litter Amendment.

Aluminum sulfate (alum) additions to poultry litter have been shown to dramatically reduce both ammonia (NH₃) emissions and phosphorus (P) runoff from poultry litter. However, in recent years the price of alum has increased markedly, creating a need for less expensive products to control ammonia emissions. The objective of this study was to determine the effects of a new litter amendment made from alum mud, bauxite and sulfuric acid (alum mud litter amendment or AMLA) on ammonia volatilization from litter and poultry production in a poultry rearing environment. Three flocks of 1000 broilers each were used for this study. The first flock of birds was used to produce the poultry litter required for the experiment. The second and third flocks of birds were allocated in twenty pens in a completely randomized block design with four replicates of five experimental treatments: 1) Control, 2) 49 kg AMLA/100 m2 incorporated, 3) 98 kg AMLA/100 m2 incorporated, 4) 98 kg AMLA/100 m2 surface applied, and 5) 98 kg alum/100 m2 incorporated. Litter samples and ammonia flux measurements were taken from each pen at 0, 7, 14, 21, 28, 35, and 42 days. The average litter pH over the six week flock was higher in untreated litter (7.92) compared to incorporating alum (7.32) or AMLA (7.18). Litter ammonium-N concentrations were lower in untreated litter (2.93 g kg-1) than litter treated with AMLA (5.43 g N/kg) or alum (5.22 g N/kg). Alum mud litter amendment reduced overall ammonia emissions by 27 to 52% compared to untreated litter, but was not significantly different from alum (35% reduction). This study shows that AMLA is an effective litter amendment for reducing ammonia emissions and should improve the fertilizer value of poultry litter.