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Bioaerosols from concentrated animal feeding operations (CAFOs) pose potential adverse effects on the health and well-being of animals, workers, and the general public. Consequently, the topic of characterizing and mitigating bioaerosols associated with CAFOs continues to draw attention as the scale of animal production increases, especially in developing countries. This study was conducted to quantify indoor and downwind concentrations of airborne bacteria, including total bacterial count (TBC), Escherichia coli, Streptococcus, and Staphylococcus aureus, of a mechanically ventilated growing swine barn (210-head capacity) in suburban Beijing, China. The results revealed that the indoor airborne bacterial levels averaged 1.96 Ö 104 ±3.08 Ö 103 colony forming units (CFU) m-3 for TBC, 2.29 Ö 103 ±5.04 Ö 102 CFU m-3 for E. coli, 1.44 Ö 104 ±1.59 Ö 103 CFU m-3 for Streptococcus, and 9.16 Ö 103 ±1.11 Ö 103 CFU m-3 for S. aureus. The airborne microbe concentrations decreased with distance downwind of the swine barn. Specifically, at 10 m downwind, E. coli concentration decreased by more than 60%, while the other microorganisms decreased by 30% to 40%. All the bioaerosol microbes decreased by 55% to 70% at 30 m downwind. The relationships between the airborne bacterial concentration and downwind distance were depicted graphically and through linear regression equations. [ABSTRACT FROM AUTHOR]

Hoop structures have been used quite widely for animal production in the U.S. due to their lower capital costs and multi-purpose versatility. Hoop barns for grower-finisher (G-F) swine production have attracted attention in China as an alternative, environmentally friendly, and water-saving production system. This study was conducted to assess concentrations and emissions of ammonia (NH3) and greenhouse gases (GHGs) for a hoop G-F pig barn at a commercial pig operation in suburban Beijing, China. The NH3 and GHG concentrations and emissions of the facility were measured for three consecutive days during spring and summer seasons. The results revealed the following hourly gaseous concentrations (mean ± SD, mg m-3): 5.9 ± 2.7 NH3, 2,183 ± 1,376 CO2, and 4.0 ± 2.5 CH4 in spring, and 6.8 ± 3.4 NH3, 1,530 ± 364 CO2, and 5.0 ± 2.3 CH4 in summer. The estimated gaseous emissions averaged, in g pig-1 d-1, 22.7 NH3, 2,003 CO2, and 6.7 CH4, or in g AU-1 d-1 (AU = 500 kg), 124 NH3, 11,264 CO2, and 36.2 CH4. The emission values from this study, while being generally comparable with those reported in the literature, add new information concerning emissions from alternative swine housing system. [ABSTRACT FROM AUTHOR]

Abstract: Gaseous emissions from animal feeding operations may be influenced by production stage, genetics, dietary type and nutritional plan, housing type, manure handling schemes, and climatic conditions. This study was conducted to quantify annual emission rates (ERs) of greenhouse gases (GHGs)—methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O) from naturally ventilated swine gestation (GE), farrowing (FA), nursery (NU) and growing-finishing (GF) barns under typical operational conditions in suburban Beijing, China. Variables relative to the GHG ERs were measured every two months for a one-year period, with each measurement episode lasting 72h. Air exchange rate of the naturally ventilated barns was estimated using CO2 balance method. The annual mean daily GHG ERs (mean SD), expressed in live body weight), for the GE, FA, NU, and GF barns were, respectively, and for CO2; and for CH4; and and for N2O. The GHG ER values from the current study paralleled those reported in the literature in some cases but differed considerably in other cases. This outcome of similarity and disparity confirms the need to exercise caution when applying literature data to estimation of GHG emissions under various production systems. Results of this study are expected to contribute to the global GHG inventory. [Copyright &y& Elsevier]