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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Egg Safety & Quality Research » Research » Publications at this Location » Publication #327716

Research Project: Reduction of Invasive Salmonella enterica in Poultry through Genomics, Phenomics and Field Investigations of Small Multi-Species Farm Environments

Location: Egg Safety & Quality Research

Title: Flue-gas desulfurization gypsum effects on urea-degrading bacteria and ammonia volatilization from broiler litter.

Author
item Burt, Christopher
item Cabrera, Miguel
item Rothrock, Michael

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/2/2017
Publication Date: 5/6/2017
Citation: Burt, C.D., Cabrera, M.L., Rothrock Jr, M.J. 2017. Flue-gas desulfurization gypsum effects on urea-degrading bacteria and ammonia volatilization from broiler litter. Poultry Science. doi:10.3382/ps/pex044.

Interpretive Summary: A major concern of the broiler industry is the volatilization of ammonia (NH3) from the mixture of bedding material and broiler excretion that covers the floor of broiler houses. Gypsum has been proposed as a litter amendment to reduce NH3 volatilization, but reports of NH3 abatement vary among studies and the mechanism responsible for decreasing NH3 volatilization is not well understood. The goal of this study was to evaluate the effect of adding 20 or 40% flue-gas desulfurization gypsum (FGG) to broiler litter on pH, electrical conductivity (EC), water potential, ureolytic bacteria abundance, NH3 and carbon dioxide (CO2) evolution, and nitrogen (N) mineralization in several 21-d experiments. The addition of FGG to broiler litter increased EC by 24 to 33%, decreased ureolytic bacteria by 48 to 57% and increased N mineralization by 10 to 11% as compared to litters not amended with FGG. Furthermore, the addition of FGG to broiler litter decreased NH3 volatilization by 18 to 28%, potentially resulting from the significantly lower litter pH values (0.09 – 0.17 pH units) compared to un-amended litter. Findings of this study indicate that amending broiler litter with 20% FGG is a low-cost strategy to decrease NH3 volatilization and increase the fertlizer value of broiler litter.

Technical Abstract: A major concern of the broiler industry is the volatilization of ammonia (NH3) from the mixture of bedding material and broiler excretion that covers the floor of broiler houses. Gypsum has been proposed as a litter amendment to reduce NH3 volatilization, but reports of NH3 abatement vary among studies and the mechanism responsible for decreasing NH3 volatilization is not well understood. The goal of this study was to evaluate the effect of adding 20 or 40% flue-gas desulfurization gypsum (FGG) to broiler litter on pH, electrical conductivity (EC), water potential, ureolytic bacteria abundance, NH3 and carbon dioxide (CO2) evolution, and nitrogen (N) mineralization in several 21-d experiments. The addition of FGG to broiler litter increased EC by 24 to 33%, decreased ureolytic bacteria by 48 to 57% and increased N mineralization by 10 to 11% as compared to litters not amended with FGG. Furthermore, the addition of FGG to broiler litter decreased NH3 volatilization by 18 to 28%, potentially resulting from the significantly lower litter pH values (0.09 – 0.17 pH units) compared to un-amended litter. Findings of this study indicate that amending broiler litter with 20% FGG is a low-cost strategy to decrease NH3 volatilization and increase the fertlizer value of broiler litter.