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Detection of Airbore Aerobic Bacteria and the Occurrence and Spread of Escherichia Coli Aerosols from Environment of Pig Houses

Author: YuanWen
Tutor: ChaiTongJie
School: Shandong Agricultural University
Course: Preventive Veterinary Medicine
Keywords: Airborne aerobic bacteria Seasonal changes Particle size distribution characteristics Potential threat E. coli aerosol ERIC-PCR
CLC: S858.28
Type: Master's thesis
Year: 2010
Downloads: 67
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Abstract

The microbial aerosol is one of the important factors Chuqin environmental pollution aerosols of biological pollution can cause a range of infectious diseases. Animal Building airborne microorganisms, mainly concentrated in a specific period of time and certain pathogens. Animal Building airborne aerobic dynamic changes throughout the year, the distribution law and its propagation characteristics involving less. Therefore, this study in Shandong Province, the most common enclosed and semi-enclosed pig for the study to detect airborne aerobic bacteria in their environment, from March 2008 to February 2009, and its distribution characteristics and hazards analysis and assessment; indicator bacteria E. coli and use the ERIC (Enterobacterial Repetitive Intergenic Consensus) the characteristics of the sequence and the differences of different antibiotic resistance, to analyze the homology of the different sources of E. coli, thereby reveal the characteristics of microbial aerosol transmission. The experiment from March 2008 to February 2009, a 5% blood agar sampling medium Andersen-6 level of microbial air samplers to collect the pigsty environment in air samples, and culture count analysis of airborne required oxygen bacteria dynamic changes of the concentration and size distribution characteristics. Closed pig house airborne aerobic bacteria concentration 9.07 × 10 ~ 4 ~ 28.23 × 10 ~ 4 CFU / m ~ 3 air; semi-closed pig house airborne aerobic bacteria concentration of 12.02 × 10 ~ 4 ~ 24.95 × 10 ~ 4 CFU / m ~ 3 air. Highest in winter and lowest in summer. Airborne aerobic bacteria are mainly distributed in the sampler AD level F level at least. The pigsty environment airborne aerobic bacteria content is not only high, and seasonal fluctuations, there are about 4.0 × 10 ~ 5 CFU and 4.9 × 10 ~ 6 CFU airborne aerobic bacteria can enter and pig small to bronchial or a direct invasion of the alveoli, which pose a potential threat to the health of human and pig. Using the same business day from pig feces, hires outside air isolated E. coli strains, each sampling point 10 of norfloxacin (NOR), cefoperazone (CFP), chloramphenicol (CMP ), composite sulfonamides (SXT), gentamicin (GEN), streptomycin (STR), tetracycline (TET), rifampicin (RIF), erythromycin (ERY), penicillin (PG), properly cloth mildew The hormone (TOB), nitrofurantoin (Ni) 12 susceptibility paper, Determination of resistance. The results showed that the strains isolated in the wind in the air the barn outside homes under RIF, ERY, PG resistant, which to a certain extent can prove Chenet microbial aerosols including drug-resistant bacteria can exchange with the gas spread to surrounding environment, so that the surrounding environment microbial contamination. Andersen-6 stage air microbial sample collection and RCS-centrifugal sampler on wind 10,50 m and downwind 10,50,100,200,400 m distance in four pig farms in indoor air, homes E. coli aerosol was collected to calculate the concentration of each sampling point of the E. coli; At the same time, acquisition of pig manure, separating E. coli. Identification techniques, ERIC-PCR amplification of the DNA bands of the different measuring points collected E. coli, the formation of the clustering Spectrum. E. coli genetic similarity analysis by each sampling point separation as well as E. coli concentration comparison, the to confirm of animal homes microbial aerosols to homes outside environment propagation mode. The results showed: E. coli in the four farms indoor air concentration of 21 ~ 35 CFU / m ~ 3 air homes upwind and homes outside under wind at much higher than the E. coli concentration (P lt; 0.05), but homes outside downwind distance between the E. coli concentration difference was not significant (P gt; 0.05). ERIC-PCR results showed that 52.4% of faecal coliform (four pig: 2/4, 50%; 2/4, 50%; 3/6, 50%; 4/7, 57.1%) with discounted The similarity of E. coli in the air can reach more than 90% up to 90% similarity; homes outside under the direction of the wind isolated from farms majority of E. coli (55%) with discounted air or separation of E. coli in the feces. It follows that the majority of E. coli isolated from upwind is not derived from animal feces or discounted air, many under the direction of the wind from the indoor air and rounding isolated E. coli from the feces of animals, animal origin homes through microbial aerosols homes inside and outside the gas exchange to spread to homes, therefore, must take effective measures to control and reduce microbial aerosol spread to the surrounding environment.

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CLC: > Agricultural Sciences > Livestock, animal medicine,hunting,silkworm,bee > Animal Medicine ( Veterinary Medicine) > Livestock, poultry, wildlife diseases > Livestock > Pig
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