Thesis (MSc (Prod. Animal studies))--University of Pretoria, 2004. / Includes bibliographical references.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed on Sept. 12, 2006). PDF text of dissertation: 181 p. : ill. ; 0.58Mb. UMI publication number: AAT 3208124. Includes bibliographical references. Also available in microfilm, microfiche and paper format.

Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 95-107). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2003. / Typescript. Includes bibliographical references (leaves 95-107). Also available on the Internet.

The Tapered Element Oscillating Microbalance (TEOM) sampler is an EPA approved Federal Equivalent Method Sampler for measuring PM10 concentrations. The Center for Agricultural Air Quality Engineering and Science (CAAQES) owns two Rupprecht and Patashnick (R&P) Series1400a monitors. The R&P Series 1400a monitor uses the TEOM method to measure particulate matter (PM) concentrations and was approved by EPA in 1990 as an automated equivalent method PM10 sampler. Since its approval, many state air pollution regulatory agencies (SAPRAs) have located R&P Series 1400a monitors at community-oriented monitoring sites. Some SAPRAs have even located TEOM samplers at the property line of major sources to determine if the source is meeting its permit requirements for PMc emissions. This thesis presents the results of PM10 and TSP concentrations measured with TEOM and low-volume gravimetric samplers at two Texas cattle feedlots. The purpose of this research was to compare the performance of the R&P Series 1400a monitor to the low-volume gravimetric sampler when sampling PM from a feedlot. Furthermore, this research was conducted to avoid the inappropriate regulation of cattle feedlots that may occur in the future as a consequence of the TEOM sampler being used to measure PMc emissions. The results of this research demonstrate that relationship between the R&P Series 1400a monitor and the low-volume gravimetric sampler is linear. In general, it was observed that the TEOM sampler measured higher PM10 and TSP concentrations than the low-volume gravimetric sampler when sampling downwind from a cattle feedlot. The opposite results were observed when sampling was conducted upwind from the feedlot. The collected data demonstrates that the concentration difference between the two sampling methods is linearly dependent with the concentration intensity for the upwind sampling locations. This trend was shown to be statistically significant. Another linear relationship was observed between the concentration difference and the particle size (mass median diameter and geometric standard deviation) of the sampled dust. Although this trend was not statistically significant, it is believed that additional downwind concentration measurements would validate this relationship.

Master of Science / Department of Biological & Agricultural Engineering / Ronaldo G. Maghirang / Large cattle feedlots in Kansas are often considered to be large sources of particulate matter (PM), including PM with equivalent aerodynamic diameter of 10 micrometers or less (PM[subscript]10). To control PM emissions from cattle feedlots, water sprinkler systems can be implemented; however, limited data are available on their PM control efficiency. This research was conducted to determine the control efficiency of a water sprinkler system in reducing PM[subscript]10 emission from a cattle feedlot. This was accomplished by monitoring the PM[subscript]10 concentrations, with tapered element oscillating microbalance (TEOM™) PM[subscript]10 monitors, at the upwind and downwind boundaries of a cattle feedlot (KS1) from January 2006 to July 2009. The feedlot was equipped with a sprinkler system that can apply up to 5 mm of water per day. It had approximately 30,000 head of beef cattle and total pen area of approximately 50 ha. The control efficiency of the sprinkler system was determined by considering the PM[subscript]10 data during sprinkler on/off events, i.e., the sprinkler system was operated (on) for at least one day and either followed or preceded by at least one day of no water sprinkling (off). For each of the selected sprinkler on/off events, the percentage reduction in net PM[subscript]10 concentration was calculated and considered to be a measure of the control efficiency. Net PM[subscript]10 concentration was defined as the difference between downwind and upwind PM[subscript]10 concentrations. The control efficiency for PM[subscript]10 ranged from 32% to 80%, with an overall mean of 53% based on 24-h PM[subscript]10 values for 10 sprinkler on/off events. In general, the effect of the water sprinkler system in reducing net PM[subscript]10 concentration lasted for one day or less. The percentage reduction in net PM[subscript]10 concentration at KS1 due to rainfall events was also determined using a similar approach. In addition, a second cattle feedlot (KS2) that was not equipped with a sprinkler system and with approximately 25,000 head of beef cattle and 68 ha pen area was considered. Percentage reductions in net PM[subscript]10 concentrations due to rainfall events were mostly in the range of 60% to almost 100% for both feedlots, with overall means of 75% for KS1 and 74% for KS2. The effects of rainfall events (with rainfall amounts > 10 mm/day) lasted for three to seven days, depending on rainfall amount and intensity. Limited data are also available on PM[subscript]10 emission rates from cattle feedlots in Kansas. This research quantified PM[subscript]10 emission rates from the two feedlots (KS1 and KS2) and a third cattle feedlot (KS3) in Kansas by using inverse dispersion modeling with the AMS/EPA Regulatory Model (AERMOD), which is the US EPA preferred regulatory atmospheric dispersion model. PM[subscript]10 emission rates were back-calculated using the resulting PM[subscript]10 concentrations modeled by AERMOD, together with measured PM[subscript]10 concentrations (24 months of data for KS1 and KS2, 6 months of data for KS3). Overall mean PM[subscript]10 emission fluxes for the 2-year period were 1.29 g/m[superscript]2-day (range: 0.04 – 4.98 g/m[superscript]2-day) for KS1, 1.03 g/m[superscript]2-day (range: 0.07 – 4.52 g/m[superscript]2-day) for KS2, and 2.48 g/m[superscript]2-day (6-months; range: 0.05 – 5.00 g/m[superscript]2-day) for KS3. The corresponding mean PM[subscript]10 emission factors were 21, 29, and 48 kg/1,000 hd-day for KS1, KS2, and KS3, respectively. The emission factors for KS1 and KS2 were considerably smaller than the published US EPA emission factor for cattle feedlots (i.e., 42 kg/1000 hd-day). The emission factor for KS3 was slightly greater than the US EPA emission factor; however, it was a biased estimate because it was based only on a six-month period.

Master of Public Health / Department of Diagnostic Medicine/Pathobiology / John A. Pickrell / Beef cattle feed lots produce significant, local point source pollution of the atmosphere. The dusts generated in the CAFOs are complex mixture of fine and ultra fine particles, organic compounds, transition metals, and adsorbed toxic gases. Since each component is toxic in itself, we do not fully understand the relative importance of each component in the dust and their interactions to inducing inflammatory changes in the lung. We did extensive literature searches to understand the mechanism of dust toxicity in respiratory system. This lead to focusing on solubility of dust in lung simulant fluid, and in-vitro study of release of two common biomarkers of inflammatory processes IL-6 and IL-8 from lung epithelial cells. Various concentrations (1 to 50%) of the dust extract induced release of IL-6, and IL-8 from lung epithelial cell as indicators of pro-inflammatory changes (IL-6), and amplification and maintenance of inflammation (IL-8). IL-6 release had dose dependence; peak production was seen with 25% dust extract. IL-8 production went down as the concentration of the dust extract increased from 1% to 25%. However, 50% dust extract was cytotoxic to the cell leading to 10-15% cell viability. At non-cytotoxic concentrations for lung epithelial cells, production of IL-8 was reduced. These findings suggested that higher exposure concentration were required to initiate inflammation as indicated by IL-6 release. Lower exposure concentrations (1 and 5% extracts) were related to optimal release of IL-8 needed to amplify and maintain the inflammatory response. Inhibition of endotoxin didn't significantly change the pattern of IL-6 or IL-8 release from epithelial cells. This finding suggested that at least a portion of the mechanism by which particle induced cytokine release from the lung epithelial cells was not endotoxin dependent. Heating samples at 1200C for 5 minutes modified some of the toxic properties of the dust extracts but didn't completely detoxify it. We observed that longer incubation period was required to peak release for both IL-6 and IL-8. However, the higher concentration of sample (50% extract) found to be cytotoxic in non-heat treated sample was no longer cytotoxic and induced both IL-6 and IL-8 release from the lung epithelial cells. This result suggested that heat treatment could reduce some of the dust extract's cytotoxic properties. However, the extract's potential to induce peak cytokine release increased.

Master of Science / Department of Biological & Agricultural Engineering / Ronaldo G. Maghirang / Large cattle feedlots emit considerable amounts of particulate matter (PM), including TSP (total suspended particulates), PM[subscript]10 (PM with equivalent aerodynamic diameter of 10 μm or less), and PM[subscript]2.5 (PM with equivalent aerodynamic diameter of 2.5 μm or less). Particulate emissions result from pen surface disturbance by cattle hoof action, vehicle traffic on unpaved roads and alleyways, and wind erosion. Research is needed to determine concentrations of various size fractions, size distribution, and emission rates from various sources in feedlots. This research was conducted to measure particle size distribution using laser diffraction method and estimate emissions from unpaved roads and wind erosion. Particle size distribution and concentrations of PM[subscript]10 and PM[subscript]2.5 at a commercial cattle feedlot in Kansas (Feedlot 1) were measured over a 2-yr period. The feedlot had a capacity of 30,000 head and total pen area of 50 ha and was equipped with a sprinkler system for dust control. Collocated low-volume samplers for TSP, PM[subscript]10, and PM[subscript]2.5 were used to measure concentrations of TSP, PM[subscript]10, and PM[subscript]2.5 at the upwind and downwind edges of the feedlot. Dust samples that were collected by TSP samplers were analyzed with a laser diffraction analyzer to determine particle size distribution. Particle size distribution at the downwind edge of the feedlot was also measured with micro-orifice uniform deposit impactor (MOUDI). The laser diffraction method and MOUDI did not differ significantly in mean geometric mean diameter (13.7 vs. 13.0 μm) but differed in mean geometric standard deviation (2.9 vs. 2.3). From laser diffraction and TSP data, PM[subscript]10 and PM[subscript]2.5 concentrations were also calculated and were not significantly different from those measured by low-volume PM[subscript]10 and PM[subscript]2.5 samplers (122 vs. 131 μg/m[superscript]3 for PM[subscript]10; 26 vs. 35 μg/m[superscript]3 for PM[subscript]2.5). Both PM[subscript]10 and PM[subscript]2.5 fractions decreased as pen surface moisture contents increased, while the PM[subscript]2.5/PM[subscript]10 ratio did not change much with pen surface moisture content. Published emission models were used to estimate PM[subscript]10 emissions from unpaved roads and wind erosion at Feedlot 1 and another nearby feedlot (Feedlot 2). Feedlot 2 had a capacity of 30,000 head, total pen surface area of 59 ha, and used water trucks for dust control. Estimated PM[subscript]10 emissions from unpaved roads and wind erosion were less than 20% of total PM[subscript]10 emissions obtained from inverse dispersion modeling. Further research is needed to establish the applicability of published emission estimation models for cattle feedlots.

Master of Science / Department of Agronomy / Gary M. Pierzynski / Soil chemical and physical properties beneath cattle feedlot pens are largely unstudied. This project was conducted to survey select soil chemical and physical properties of soil beneath active open air cattle feedlots. At four cattle feedlots in Kansas, the concentrations of NH4-N, organic-N, organic-C, Cl-, and P were high at the surface and rapidly decreased within 1.00 m. At three of the four feedlots, NO3-N was generally below background concentration (4.1 mg kg-1) while one feedlot had a >75 mg kg-1 increase in the top 1.00 m. Based on feeding data, only a small percent (7.9 to 1.2) of the total N deposited on the surface was found in the top 1.00 m below the pen surface for a range of 25 to 60 years of operation. While in use, these feedlots do not appear to have a high potential for groundwater pollution from NO3-N leaching. However, if they were to become inactive they may pose a severe threat to groundwater quality from organic-N mineralization and NH4-N nitrification. If feedlots were closed and the land could be largely remediated by removing a layer of soil, these feedlots would have an average 48% profile N removed in a 0.25 m thick layer. A chamber, a modified vacuum desiccator, was tested for the investigation of NH3 volatilization from soil in the laboratory. Ammonia volatilization at the soil surface is dependent on air flow, soil and air temperatures, soil water content, pH, the concentrations of NH3 and NH4+ in the air and soil solution, and factors affecting soil temperature including humidity. This chamber was built to control and/or quantify as many of these variables as possible. A technique for quantifying and predicting NH3 volatilization is important because AFOs are one of the largest contributors of NH3 to the atmosphere, which can cause acid precipitation and particulate matter deposition downwind from the operation. The chambers created allowed for repeated measurements with little error and appear to be a feasible, inexpensive apparatus to investigate NH3 volatilization mechanisms. Using synthetic urine as an N source, NH3 volatilization was affected by initial soil moisture content and soil texture and may be affected by initial soil pH. This chamber has promise to provide excellent data to assist the efforts being made to understand and model NH3 volatilization from feedlot pens.