Concentrations and Size Distributions of Airborne Particulate Matter and Bacteria in an Experimental Aviary Laying-Hen Chamber

摘要: Abstract. High levels of airborne particulate matter (PM) and bacteria may exist in animal housing, which can be detrimental to the health animals workers. The sizes these bioaerosols determine their aerial transport behaviors depositions respiratory tracts humans. However, little is known regarding size distribution PM livestock houses, especially alternative housing systems that aim enhance welfare, such as aviary hen-housing systems. study reported here was therefore conducted characterize concentrations distributions (in count) (both count mass) a pilot-scale laying-hen chamber. Thirty-four laying hens were kept environmentally controlled chamber (L A— W H = 2.2 2.3 2.4 m) for three months. given 16L:8D photoperiod (lights on at 6:00 h off 22:00 h) access litter floor from 12:00 daily. Airborne simultaneously sampled 15 min 1.5 m above every fourth day 5:45 h, 9:45 13:45 17:45 21:45 h. Concentrations six ranges (0.65 1.1 I¼m, 2.1 3.3 4.7 7.1 >7.1 I¼m) (0.523 20.535 determined. daily mean (±SD) count, mass, 1.70 (±0.66) 10 7 particles -3 , 1.12 (±0.47) mg 3.39 (±2.38) 5 cfu respectively. during litter-access period (12:00 significantly higher than those rest when (p 2.5 I¼m accounted more 90% total range 0.523 I¼m. majority (>95%) carried by >3.3 concentration positively related mass -1 PM. Results are useful improving understanding aerosols hen systems, assessing potential risks humans animals, exploring mitigation techniques.