Impacts of feeding dried distillers grains with solubles on aerial emissions when fed to swine

In recent years the corn grain ethanol industry has expanded and led to increased availability of dried distillers grains with solubles (DDGS), and feeding DDGS to swine is becoming more common in pork production. With feed being the primary cost in pork production and increasing interest in air emissions from animal feeding operations, it is important to understand the impacts of non-traditional dietary formulations on aerial emissions. The purpose of this study was to evaluate the impacts of feeding DDGS on ammonia (NH3), hydrogen sulfide (H2S) and greenhouse gas (GHG) emissions from deep-pit swine wean-to-finish (5.5 - 118 kg) facilities in Iowa, the leading swine producing state in the USA. To attain the study objectives, two commercial, co-located wean-to-finish barns were monitored: one barn received a traditional corn-soybean meal diet (designated as Non-DDGS regimen), while the other received a diet that included 22% DDGS (designated as DDGS regimen). Gaseous concentrations and barn ventilation rate (VR) were monitored or determined semi-continuously, and the corresponding emission rates (ER) were derived from the concentration and VR data. Two turns of production were monitored for this study, covering the period of December 2009 to January 2011. The daily and cumulative emissions are expressed on the basis of per barn, per pig, and per animal unit (AU, 500 kg live body weight). Results from this project indicate that feeding 22% DDGS does not significantly affect aerial emissions of NH3, H2S, CO2, N2O or CH4 when compared to the Non-DDGS regimen in a deep-pit wean-to-finish swine facility (p-value = 0.10 for NH3, 0.13 for H2S, 0.55 for CO2, 0.58 for N2O, and 0.18 for CH4). ER for the Non-DDGS regimen, in g/d-pig, averaged 7.5 NH3, 0.37 H2S, 2127 CO2 and 72 CH4. In comparison, ER for the DDGS regimen, in g/d-pig, averaged 8.1 NH3, 0.4 H2S, 1849 CO2, and 48 CH4. On the basis of kg gas emission per AU marketed, the values were 8.7 NH3, 0.724 H2S, 2350 CO2 and 84 CH4 for the Non-DDGS regimen; and 12 NH3, 0.777 H2S, 2095 CO2, and 60 CH4 for the DDGS regimen. Results of this extended field-scale study help filling the knowledge gap of GHG emissions from modern swine production systems

Physical and Chemical Properties of Runoff Effluent from Beef Feedlots in Iowa

Beef feedlot runoff is a potential environmental contaminant. As such, it should be managed properly to preserve water quality. Primary treatment of feedlot runoff often relies on sedimentation techniques; thus, accurate knowledge of feedlot runoff physical properties is required. This study characterized the physical and chemical properties of runoff effluent from earthen and concrete beef feedlots in Iowa with the objective of providing the necessary information to improve solid settling basin design and performance. Results, although not statistically significant (p = 0.11), indicated that solids in runoff from concrete lots tended to settle more slowly than solids from earthen lots. Particle size distribution and particle density measurements indicated that the poorer settleability of concrete lot runoff was primarily caused by lower particle densities: 1.47 ±0.17 g cm-3 (average ± SD) for concrete lots as compared to 1.89 ±0.11 g cm-3 for earthen lots. Runoff composition was analyzed before and after settling to relate nutrient reduction to solids removal. Results indicated an average of 41 g total Kjeldahl nitrogen per kg total solids and 16 g total phosphorus per kg total solids were removed during settling

Physical and Chemical Properties of Runoff from Beef Feedlots in Iowa

Beef feedlot runoff is a potential environmental contaminant. As such, its proper management is required to preserve water quality. Primary treatment of feedlot runoff often relies on sedimentation techniques, thus accurate knowledge of feedlot runoff physical properties is required. This study characterized the physical and chemical properties of runoff effluent from earthen and concrete beef feedlots in Iowa with the objective of providing the necessary information to improve solid settling basin design and performance. Study results indicated there was a difference between the settleability of runoff from earthen and concrete lots. Particle size distribution and particle density measurements indicated that the poorer settleability of concrete lot runoff was primarily caused by lower particle densities, 1.47±0.17 g/cm3 for concrete lots as compared to 1.89 ± 0.11 g/cm3 for earthen lots. Runoff composition was analyzed before and after settling to relate nutrient reduction to solids removal. Results indicate an average of 41 g-TKN/kg-TS and 16 g-TP/kg-TS removed by settling

Fourth-Generation Fan Assessment Numeration System (FANS) Design and Performance Specifications

The Fan Assessment Numeration System (FANS) is a measurement device for generating ventilation fan performance curves. Three different-sized FANS currently exist for assessing ventilation fans commonly used in poultry and livestock housing systems. All FANS consist of an array of anemometers inside an aluminum shroud that traverse the inlet or outlet of a ventilation fan. The FANS design has been updated several times since its inception and is currently in its fourth-generation (G4). The current design iteration (FANS-G4) is reported in this article with an emphasis on the hardware and software control, data acquisition systems, and operational reliability. Six FANS-G4 units were fabricated at the University of Kentucky (UK) Agricultural Machinery Research Laboratory and calibrated at the University of Illinois Urbana-Champaign (UIUC) Bioenvironmental and Structural Systems (BESS) Laboratory. Results demonstrated that the FANS-G4 was capable of measuring volumetric airflow to within 0.6% of full-scale (FS), which ranged from 15,000 to 56,000 m3 h-1

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

Nutrients excreted from animals affect the nutritive value of manure as a soil amendment as well as the composition of gases emitted from manure storage facilities. There is a dearth of information, however, on how diet type in combination with dietary particle size affects nutrients deposited into manure storage facilities, and how this subsequently affects manure composition and gas emissions. To fill this knowledge gap, an animal feeding trial was performed to evaluate potential interactive effects between feed particle size and diet composition on manure characteristics and manure‐derived gaseous emissions. Forty eight finishing pigs housed in individual metabolism crates which allowed for daily collection of urine and feces were fed diets differing in fiber content and particle size, with their urine and feces collected and stored in 446 L stainless steel containers over a period of 49 d. 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 nitrogen (N), carbon (C), and total volatile fatty acid (VFA) concentrations, and increased manure VFA emissions, but decreased manure ammonia emissions. Decreasing the particle size of the diet lowered manure N, C, VFA, phenolics, and indole concentrations, and decreased manure emissions of total VFA. Neither diet composition nor particle size had an impact on manure greenhouse gas emissions (GHG)

A Comparison of Gaseous Emissions from Swine Finisher Facilities Fed Traditional vs. A DDGS-Based Diet

Expansion of the corn grain ethanol industry has led to increased availability of dried distillers grains with solubles (DDGS), and feeding DDGS to swine is becoming more common in pork production. Because feed is the primary cost in pork production and interest in air emissions from animal feeding operations is increasing, it is important to understand the impacts of non-traditional dietary formulations on aerial emissions. The purpose of this study was to identify and quantify the impacts of feeding DDGS on gaseous emissions from deep-pit swine finisher operations. To complete the study, two full-scale, commercial, co-located swine barns were monitored; one of the barns received a traditional diet, and the other received a diet that included DDGS. The constituents measured during this project were ammonia (NH3), hydrogen sulfide (H2S), and greenhouse gases (GHG) (carbon dioxide – CO2, nitrous oxide – N2O, and methane – CH4). At the time of this writing, results from this study indicated feeding 22% DDGS increased aerial NH3 emission from 3.1 g/pig-d to 4.6 g/pig-d and H2S emissions from 0.10 g/pig-d to 0.19 g/pig-d, but had no effect on GHG

Ammonia, Hydrogen Sulfide, and Greenhouse Gas Emissions from Wean-to-Finish Swine Barns Fed Diets with or without DDGS

In recent years the corn grain ethanol industry has expanded and led to increased availability of dried distillers grains with solubles (DDGS). As a result, feeding DDGS to swine is becoming more common in pork production. With feed being the primary cost in pork production and increasing interest in air emissions from animal feeding operations, it is important to understand the impacts of non-traditional dietary formulations on aerial emissions. The purpose of this study was to evaluate the impacts of feeding DDGS on ammonia (NH3), hydrogen sulfide (H2S) and greenhouse gas (GHG) emissions from deep-pit swine wean-to-finish (5.5 – 118 kg) facilities in Iowa, the leading swine producing state in the USA. To attain the study objectives, two commercial, co-located wean-to-finish barns were monitored: one barn received a traditional corn-soybean meal diet (designated as Non-DDGS regimen), while the other received a diet that included 22% DDGS (designated as DDGS regimen). Gaseous concentrations and barn ventilation rate (VR) were monitored or determined semi-continuously, and the corresponding emission rates (ER) were derived from the concentration and VR data. Two turns of production were monitored for this study, covering the period of December 2009 to January 2011. The daily and cumulative emissions are expressed on the basis of per barn, per pig, and per animal unit (AU, 500 kg live body weight). Results from this project indicate that feeding 22% DDGS does not significantly affect aerial emissions of NH3, H2S, CO2, N2O or CH4 when compared to the Non-DDGS regimen in a deep-pit wean-to-finish swine facility (p-value = 0.10 for NH3, 0.13 for H2S, 0.55 for CO2, 0.58 for N2O, and 0.18 for CH4). ER for the Non-DDGS regimen, in g/d-pig, averaged 7.5 NH3, 0.37 H2S, 2127 CO2 and 72 CH4. In comparison, ER for the DDGS regimen, in g/d-pig, averaged 8.1 NH3, 0.4 H2S, 1849 CO2, and 48 CH4. On the basis of kg gas emission per AU marketed, the values were 8.7 NH3, 0.724 H2S, 2350 CO2 and 84 CH4 for the Non-DDGS regimen; and 12 NH3, 0.777 H2S, 2095 CO2, and 60 CH4 for the DDGS regimen. Results of this extended field-scale study help filling the knowledge gap of GHG emissions and impact of DDGS on gaseous emissions from modern swine production systems

Validation of a Low Cost Flow Measurement System for Monitoring Vegetative Treatment System Performance

In 2006, the Iowa Department of Natural Resources issued National Pollution Discharge Elimination System (NPDES) permits to six feedlots participating in research on the use of vegetative treatment systems (VTSs) to control beef feedlot runoff. While Iowa State University monitors releases from the research portion of these sites, the producers are required to monitor releases from the non-research portions. Additionally, non-research site producers with VTSs and NPDES permits are required to monitor system releases. They are required to measure release volume and collect a sample for analysis. Automated, research oriented open channel flow measurement systems typically cost $7,500 to employ. Muhlbauer et. al (2007) developed a low cost monitoring system (LMS) designed to measure open channel flow from a VTS with a total cost of$1,600. Testing of the LMS by Muhlbauer et. al. (2007) across flow events ranging from one to six hours indicated a mean accuracy of 90.6% in comparison to a flow meter equipped ISCO 6712 portable sampler using a .46m (18”) fiberglass H-flume. Further cost reduction options for a producer include fabrication of a metal H-flume, reducing total system cost to $850. This paper compares the performance of the LMS for estimating both short and longer duration flow events and performance of the fabricated metal flume. The LMS flow measurements were compared to an ISCO 6712 portable sampler and a Krohne Optiflux 4000 flow meter in twelve field tests lasting one and six hours with an accuracy of 88.5% in comparison to the Krohne. Relative to a commercial fiberglass flume, the three fabricated flumes had a mean percent accuracy of 98%

An Evaluation of the Physicochemical and Biological Characteristics of Foaming Swine Manure

Foam accumulation in deep-pit manure storages is an increasing concern for swine producers because of the logistical and safety-related problems it creates. To investigate this phenomenon, samples of swine manure were collected over a 13-month period from 58 swine production facilities in Iowa with varying levels of foam accumulation. Samples were tested for a number of physical, chemical, and biological parameters including pH, total and volatile solids, volatile fatty acid concentration, long-chain free fatty acid concentration, biochemical methane potential, methane production rate, surface tension, foaming capacity, and foam stability. Statistical analysis indicated that manure collected from facilities with foam accumulation produced methane at significantly (p \u3c 0.05) faster rates than non-foaming manures (0.148 ±0.004 and 0.049 ±0.003 L CH4 L-1 slurry d-1, respectively) and consequently had significantly (p \u3c 0.05) greater fluxes of biogas moving through the manure. The biochemical methane production assay suggested that manure from foaming pits had less potential to generate methane (123 ±9 mL CH4 g-1 VS) than manure from non-foaming pits (150 ±9 mL CH4 g-1 VS), presumably because more of the methane potential had previously been consumed, as indicated by the higher methane production rates. Short-chain fatty acid concentrations were significantly lower in foaming manures (4200 ±570 mg kg-1) than non-foaming manures (9470 ±730 mg kg-1). The methane production rate, biochemical methane potential, and short-chain fatty acid assays suggest enhanced anaerobic digestion efficiency from foaming barns as compared to non-foaming barns. Other assays, such as surface tension and foaming capacity, indicated an accumulation of a surfactant at the manure-air interface of the foam, which may be capturing biogas bubbles generated within the manure. Most importantly, the foam layers exhibited a greatly enhanced ability to stabilize bubbles, which appeared to be correlated to the higher solids concentrations that stabilize the bubbles

Impact of Dietary Carbohydrate and Protein Source and Content on Swine Manure Foaming Properties

Diet ingredients are thought to contribute to foaming problems associated with swine manure stored in deep-pit systems. Two experiments explored the impact of protein and carbohydrate sources and levels in swine diets on the physicochemical properties, methane production potential, and foaming potential of swine manure. The first experiment was specific to protein and evaluated the impact of dietary protein level and source on manure properties, while the second experiment focused on evaluating the impact of different dietary carbohydrate sources on manure foaming properties. Manure from the animals was tested for total and volatile solids, methane production rate and biochemical methane potential, surface tension, foaming capacity and stability, and microbial community structure. No single diet yielded manure with all of the anticipated qualities associated with foaming manure. However, manure collected from pigs fed diets containing soy hulls and distillers dried grains with solubles (DDGS) exhibited higher methane production rates (0.95 ±0.20 and 0.96 ±0.20 L CH4 kg-1 VS, respectively) and biochemical methane potential (322 ±25 and 269 ±22 mL CH4 g-1 VS, respectively) when compared to manure obtained from pigs fed the other diets. Additionally, the results showed that both protein level and source exhibited greater influence over the microbial community than carbohydrate source, with manipulations in the protein diet leading to positive correlations with specific microbial community and higher methane production rates, foaming capacity, and foam stability. In this study, these parameters appeared to be tied to higher levels of corn, or corn protein, in the diet. Although some of the microbial community was explained by diet, this study also demonstrated that factors other than diet have significant influence on microbial community