Particulate matter concentrations for mono-slope beef cattle facilities in the Northern Great Plains

Abstract

<abstract> <bold>Abstract.</bold> Confined cattle facilities are an increasingly common housing system in the Northern Great Plains region of the United States. Producers may maintain a deep-bedded manure pack (Pack), they may remove all bedding/manure material from the pens weekly (Scrape), or use a combination of management styles. The objectives of this study were to determine baseline particulate matter (PM) concentrations around the barn perimeter, and to identify relationships between management practices and PM concentrations. Particulate matter was measured over two five-day periods at one Pack barn to determine differences in PM concentration between routine operation and bedding events. Each five-day period included three 24-h periods of routine operation and two 3-h periods associated with a bedding event. Concentration of total suspended particulates (TSP) in the Pack barn for days of routine operation was 58.6 ± 3.9 µg/m³ and concentration of TSP during three-hour bedding events was 702.2 ± 3.9 µg/m³. Concentrations of PM less than 2.5 microns (PM_2.5) and PM less than 10 microns (PM₁₀) were 4.9 ± 3.0 and 17.5 ± 12.1 µg/m³, respectively, during routine operation, and 29.7 ± 4.6 and 141.7 ± 18.9 µg/m³, respectively, during a 3-hr bedding event. In two Scrape barns, 24-h collections of PM₁₀ and PM_2.5 occurred at least twice during each quarter for 14 months. Daily mean concentrations of PM_2.5 and PM₁₀ in Scrape barns ranged from 10 – 14 µg/m³and 25 – 28 µg/m³, respectively, indicating relatively low PM concentrations from mono-slope beef facilities. Particulate matter was affected by air temperature.