| Concentration of indoor and outdoor bioaerosol including its concentration and composition were measured in different poultry farms in one year. At the same time, the quantitative relationship between the concentrations of indoor and outdoor bioaerosol was analyzed. The composition of the airborne aerobic staphylococcus cluster was identified. We can deduce the dangerous to animal and human's health in terms of the distribution of airborne microbiological aerosol particle in Anderson six-stage sampler. And we analyzed the concentration of aerobic staphylococcus in feedingstuff and feces deduced that the transmission of indoor bioaerosol and the main source of outdoor bioaerosol. Finally, analyzing aerobic staphylococcus in defferent seasons. Through this experiment, we laid the foundation to study and form a appropriate farming model of animal feeding to settle the conflict between economic benefits and environment benefits. The study consists of four parts:Part I: The concentrations of bioaerosol in poultryIn order to study the concentrations of airborne aerobic bacteria chicken houses to their ambient air, the air samples, including indoor, upwind (10m, 50m) and downwind air (10m, 50m, 100m, 200m, 400m) of 6 chicken houses were collected using Andersen-6 stages sampler and LWC-1 and 5% buck blood-blood agar foundation media served as medium. Moreover, the concentration of airborne aerobic bacteria were identified with gram-staining and API-array. The results indicated that the number of total airborne aerobic bacteria in poultry houses varied from 5.2×101 to 2.47×104CFU/m3, the number of airborne staphylococcus bacteria varied from 5.8×101 to 1.76×103 CFU/m3, the number of airborne aerobic staphylococcus aureus from 6×101 to 4.34×102CFU/m3.Moreover, the quantitative relationship between the concentrations of indoor airborne and outdoor airborne bacteria were analyzed. The results showed that the indoor airborne bacteria concentration in houses were higher than those of upwind and downwind sites (P<0.05 or P<0.01), but there were no significantly differences of airborne bacteria concentration among every downwind site (p>0.05).PartⅡ: The concentration and composition of airborne staphylococcus bacteria and its aerodynamic diameter (Dae50)In this experiment, we measured the concentration and composion of airborne staphylococcus bacteria. At first, the gram-gative bacteria was identified by using the gram-staining; Second, airborne gram-gative bacteria were pure culture on the Baird-Park agar medium and identified by API 20 Steph(Bio Merieux, Marcy-I'Etoile, France). The result showed that the percentage of staphylococcus in the total number of airborne aerobic bacterial were 8.43% to 16.61% in the poultry farms. The component of airborne staphylococcus are staphylococcus aureus,staphylococcus epidermidis,staphylococcus saprophyicus,staphylococcus hyicus,staphylococcus xylosus,staphylococcus capitis,staphylococcus cohnii and staphylococcus equorum. Among them, the content of staphylococcus aureus is about 24% and 27% of the total number of staphylococcus, staphylococcus epidermidis and staphylococcus saprophyicus are the next in order. In addition, based on the distributing in the six layers of Andersen-6 stage sampler, airborne aerobic bacterial and airborne staphylococcus aureus distributed at B to E stage with aerodynamic diameters ranged from 2μm to 6μm, which can reach trachea and bronchia even bronchiole, make severe threatening for stockmen and animals respiratory tract.PartⅢ:REP-PCR Identification of airborne staphylococcus aureus from the indoor and outdoor air in the chicken farmIn order to study the transmission of S. aureus in poultry houses to their ambient air, the air samples, including indoor, upwind (10m, 50m) and downwind air (10m, 50m, 100m, 200m, 400m) of 4 chicken houses were collected . Feces samples were collected according to the standard method and S. aureus was isolated. S. aureus was used as an indicator in this study .The repetitive extragenic palindromic elements, PCR, REP-PCR method was applied to generate genomic amplification products of S. aureus isolated from the chicken feces and the air. By analyzing the different concentration and genetic similarity of S. aureus in every sampling site, the transmission of bioaerosol from indoor houses to their ambient can be identified.The results showed that The fingerprints and the phylogenetic tree indicated that a part of the S. aureus (38.7%) isolated from indoor air had the same REP-PCR fingerprints with those isolated from feces, the most of S. aureus isolated (55.9%) from downwind 10m, 50m, 100m, 200m even 400m had the same REP-PCR fingerprints with those isolated from indoor air or feces too, which indicated that some isolates isolated from downwind air and indoor air originated in the chicken feces. So, it was concluded that the isolates isolated from upwind air didn't come from the feces or indoor air. In a word, the S. aureus in feces can be aerosolized and transmitted into the indoor air and outdoor air, especially the downwind air of the houses with the air exchange. This study can reveal the transmitting rule of airborne S. aureus bioaerosol to the ambience. Hygienic measures taking in animal farms have the significant meanings of public hygiene and epidemiology. The study measured the concentration of airborne staphylococcus in different seasons and analyzed the change between them. The results indicated that in summer the number of total airborne aerobic bacteria in poultry varied from 6.8×10 to 2.32×103CFU/m3, the number of total airborne staphylococcus bacteria in poultry varied from 5.63×102 to 2.87×104CFU/m3, the number of airborne S.aureus varied from 6 to 4.34×102CFU/m3; in autumn the number of total airborne aerobic bacteria in poultry varied from 5.2×101 to 2.35×103CFU/m3,the number of airborne staphylococcus bacteria in these farms varied from 9.4×101 to 1.47×103 CFU/m3, the number of airborne S.aureus varied from 6 to 4.24×102CFU/m3;in winter the number of total airborne aerobic bacteria in poultry varied from 6.5×101 to 2.47×104CFU/m3,the number of airborne staphylococcus bacteria varied from 5.8×101 to 1.76×103CFU/m3, the number of airborne S.aureus bacteria varied from 8 to 3.54×102CFU/m3.The number of airborne staphylococcus in poultry farms in winter was higher than those in summer and autumn. The results showed the number of airborne staphylococcus changed with seasons significantly, we should paid more attention to the disinfection and preventing in summer and autumn.
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