Wang-Li Lingjuan, Li Qianfeng, Byfield Grace E
Biological and Agricultural Engineering Department, North Carolina State University , Raleigh, North Carolina.
Environ Eng Sci. 2013 Jan;30(1):2-10. doi: 10.1089/ees.2011.0517.
This field study investigated biological characteristics of aerosols emitted from a commercial egg production farm (layer operation). Bioaerosol samples were taken on this farm at five sampling locations covering emission source (inside a layer barn) and four ambient surrounding stations at four wind directions. All-glass impingers (AGI) were used for the field sampling. AGI fluid samples were plated in duplicate on Trypticase Soy Agar for growth of bacteria and Sabouraud Dextrose Agar for growth of fungi. The most prominent bacterial colony types were identified using a combination of methods that include recording characteristics of colony morphology; performing a Gram staining method and metabolic analyses using the Biolog system. Results from thirty-five AGI samples taken at the five stations through seven sampling events over four seasons indicate that there were significantly lower total bacterial concentrations in the samples collected from ambient stations as compared with the samples collected in the layer house; the mean bacterial concentration at the in-house sampling station was 3.86×10(5)±1.74×10(5) cfu/m(3), whereas the mean bacterial concentrations at four ambient stations in the vicinity of the farm ranged from 1.3×10(3) to 6.2×10(3) cfu/m(3) with no significant differences in mean among ambient stations. There were also no significant differences in fungi concentrations among all sampling stations. Mean fungi concentrations at the in-house station was 3.0×10(3)±4.45×10(3) cfu/m(3), whereas the mean concentrations at the ambient stations ranged from 7.4×10(3) to 1.7×10(4) cfu/m(3). The most prominent bacterial species differed among all five stations. Three of the most prominent bacteria from samples taken at all five stations were gram positive. Fungal type also differed from station to station.
这项实地研究调查了一家商业化蛋鸡养殖场(蛋鸡养殖作业)排放的气溶胶的生物学特性。在该养殖场的五个采样地点采集了生物气溶胶样本,这五个采样地点涵盖了排放源(蛋鸡舍内部)以及四个风向的四个周边环境监测站。使用全玻璃冲击式采样器(AGI)进行实地采样。将AGI液体样本一式两份接种在胰蛋白胨大豆琼脂上用于细菌培养,接种在沙氏葡萄糖琼脂上用于真菌培养。使用多种方法组合来鉴定最突出的细菌菌落类型,这些方法包括记录菌落形态特征、进行革兰氏染色法以及使用Biolog系统进行代谢分析。在四个季节里通过七次采样事件在五个监测站采集的35个AGI样本的结果表明,与在蛋鸡舍采集的样本相比,从周边环境监测站采集的样本中细菌总浓度显著更低;舍内采样站的平均细菌浓度为3.86×10⁵±1.74×10⁵ cfu/m³,而养殖场附近四个周边环境监测站的平均细菌浓度在1.3×10³至6.2×10³ cfu/m³之间,各周边环境监测站之间的平均值无显著差异。所有采样站的真菌浓度也无显著差异。舍内监测站的平均真菌浓度为3.0×10³±4.45×10³ cfu/m³,而周边环境监测站的平均浓度在7.4×10³至1.7×10⁴ cfu/m³之间。所有五个监测站中最突出的细菌种类各不相同。在所有五个监测站采集的样本中,最突出的三种细菌中有三种是革兰氏阳性菌。真菌类型也因监测站而异。