Odorous volatile organic compounds, Escherichia coli, and nutrient concentrations when kiln-dried pine chips and corn stover bedding are used in beef bedded manure packs

Authors: Spiehs, Mindy; Berry, Elaine; Wells, James - Jim; Parker, David; Brown-Brandl, Tami

Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2017
Publication Date: 7/27/2017
Publication URL: https://handle.nal.usda.gov/10113/5801884
Citation: Spiehs, M.J., Berry, E.D., Wells, J., Parker, D.B., Brown-Brandl, T.M. 2017. Odorous volatile organic compounds, Escherichia coli, and nutrient concentrations when kiln-dried pine chips and corn stover bedding are used in beef bedded manure packs. Journal of Environmental Quality. 46(4):722-732. https://doi.org/10.2134/jeq2016.09.0333.

Interpretive Summary: When livestock are housed in confined places, offensive odors can be generated from the fermentation of carbohydrates and proteins in livestock waste (urine, feces, spilled feed, and bedding material). Cattle are also a reservoir of the pathogen Escherichia coli, and directly or indirectly can be a source of this pathogen for the contamination of water, soil, and produce, as well as other livestock in the production environment. Previous research from our laboratory has demonstrated that bedding material containing pine shavings produces less odors and has lower levels of total E. coli compared to bedded packs made with other crop- and wood-based bedding materials. Although there appear to be obvious benefits to using pine bedding, availability and affordability may limit the use in beef deep-bedded facilities. However, it may be possible to see some of the benefits of pine bedding if it is mixed with a readily available and affordable bedding material such as corn stover. We tested mixtures of bedding materials containing 0, 10, 20, 30, 40, 60, 80, and 100% pine chips combined with corn stover over a 7 week period to determine if the bedding material affected odor generation or presence of E. coli. Bedding material did not affect E. coli. Including even 10% pine chips in the mixture lowered the concentration of skatole, a highly odorous compound emitted from livestock waste. When 100% pine chips were used, skatole was reduced by 88% compared to using corn stover alone. However, including greater than 60% pine chips in the mixture increased the concentration of odorous sulfur compounds by up to 2.4 times over the use of corn stover. Therefore, a bedding material mixture containing 30 – 60% pine and 40 – 70% corn stover may be the ideal combination to mitigate odorous emissions from livestock facilities using deep bedded systems.

Technical Abstract: Pine (Pinus spp.) bedding has been shown to lower the concentration of odorous volatile organic compounds (VOCs) and pathogenic bacteria compared with corn (Zea mays L.) stover bedding, but availability and cost limit the use of pine bedding in cattle confinement facilities. The objectives of this study were to determine if the addition of pine wood chips to laboratory-scaled bedded packs containing corn stover (i) reduced odorous VOC emissions; (ii) reduced total E. coli; and (iii) changed the nutrient composition of the resulting manure-bedded packs. Bedding treatments included 0, 10, 20, 30, 40, 60, 80, and 100% pine chips with the balance being corn stover. Four bedded packs for each mixture were maintained for 42 d (n = 4 observations per bedding material). The production of total sulfur compounds increased significantly when 100% pine chips were used (44.72 ng L-1) compared with bedding mixture containing corn stover (18.0 – 24.56 ng L-1). The carbon-to-nitrogen ratio exceeed the ideal ratio of 24:1 for the optimum activity of soil microorganisms when >/=60% pine chips (25.3 – 27.5 ng L-1) were included in the mixture. The use of 100% pine chips as bedding increased sulfide concentration in the facility 1.8 – 2.4 times over the use of corn stover bedding. Escherichia coli was not influenced by the addition of pine chips to the corn stover bedding material but did decrease as the bedded pack aged. Bedding material mixtures containing 30 to 60% pine and 40 to 70% corn stover may be the ideal combination to mitigate odors from livestock facilities using deep bedded systems.