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ARS Home » Midwest Area » Ames, Iowa » National Laboratory for Agriculture and The Environment » Agroecosystems Management Research » Research » Publications at this Location » Publication #369721

Research Project: Reducing Production Losses due to Oxidative Stress and Bacterial Pathogens in Swine

Location: Agroecosystems Management Research

Title: Dietary composition and particle size effects on swine manure characteristics and gas emissions

item Kerr, Brian
item Trabue, Steven
item ANDERSON, DANIEL - Iowa State University
item VAN WEELDEN, MARK - Iowa State University
item PEPPLE, LAURA - University Of Illinois

Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/27/2020
Publication Date: 9/20/2020
Publication URL:
Citation: Kerr, B.J., Trabue, S.L., Anderson, D.S., Van Weelden, M.B., Pepple, L.M. 2020. Dietary composition and particle size effects on swine manure characteristics and gas emissions. Journal of Environmental Quality. 49(5):1384-1395.

Interpretive Summary: Diet composition and diet particle size can have profound implications on how energy and nutrients in a diet are digested and utilized by growing pigs; and consequently will affect manure composition and gas emissions from manure storage containers. The current study was conducted to determine if manure composition and gas emissions were impacted by diet composition and feed particle size. Data from this experiment indicates that increasing dietary fiber or increasing dietary particle size, each of which reduce digestibility, resulting in increased manure nitrogen, carbon, and total volatile fatty acid concentrations, and tending to increase manure-emissions of total volatile fatty acids. In contrast, neither diet type or particle size had an effect on manure greenhouse gas emissions. Averaged across all diet types and particle sizes, 20% of dietary carbon is retained in the body, 10% ends up in the manure, and 15% is lost in gas emissions; while for dietary nitrogen, 33% ends up in the body, 24% ends up in the manure, and 43% is lost in gas emissions. This information is important for nutritionists at universities, feed companies, and pig production facilities for determining how diet composition and diet particle size can affect manure composition and manure gas emissions.

Technical Abstract: Nutrients excreted from growing animals affect the nutritive value of manure as a soil amendment as well as the composition of gases emitted from manure storage facilities. An animal feeding trial was performed to evaluate potential interactive effects between feed particle size and diet composition on manure composition and manure-gas emissions. Two sets of 24 finishing pigs were fed and their manure collected over a period of 49 days. There were no interactive effects between diet composition and feed particle size on any manure or gas emission parameter measured. In general, diets higher in fiber content increased manure N, C, and total VFA concentration, and increased manure VFA emissions, but decreased manure NH3 emissions. Decreasing the particle size of the diet lowered manure N, C, total VFA, phenolics, and indole concentrations, and decreased manure emissions of total VFA. Neither diet composition nor particle size had an impact on manure GHG emissions.