Study On The Difference Of The Fungal Aerosol Of Sheep House With Different Structures And Different Ways Of Feeding

In the process of animal breeding,a large number of fungal aerosols will be produced,which will endanger the health of animals and humans and bring huge economic losses to the breeding industry.The concentration,composition and the degree of damage of the airborne fungi are closely related to the feeding mode and structure of animal enclosure.This study selected enclosed and semi-enclosed sheep houses,and selected two methods for breeding sheep house that net rearing and ground rearing in enclosed barn raising as the research object,which are common in Shanxi Province.Since July 2016 to December 2017,air sample were collected from inside and outside of the four types of sheep houses above of four seasons were obtained by the Andersen-6 sampler and AGI-30 sampler,and the sampling matrix is RBM and ultrapure water.Samples of feed and feces were collected at the same time.Concentration,composition,particle size distribution of aerosol fungi from different types of sheep house were determination and analyzed.By using the ERIC-PCR technique,the author compared the overall differences in the structure of the fungal flora of different types of sheep,and explored the propagation rule of the air fungi in the sheep house,so as to provide the basis for the selection of the sheep house and the environmental control.The results showed that:1.Airborne fungi concentrations from enclosed sheep house in spring and autumn was significantly higher than semi-enclosed house.Airborne fungi from two kinds of structure house on the Andersen-6 sampler were normal distribution,which were mainly distributed in sampler ?-? level(1.1-4.7?m).CMD values of sheep house airborne fungi were basically the same,but were changed with the seasons.The number of fungal aerosol particles that can reach the deep respiratory tract in enclosed sheep house was higher than the semi-enclosed sheep house,so the threat to human and animal health is greater.2.The concentration of airborne fungi in the net rearing was significantly higher than that the ground raising in the spring and summer,however,lower in winter.House airborne fungi were mainly distributed in sampler III-V level(1.1-4.7?m).The CMD of the net rearing amniotic fluid was lower than that of the ground.The maximum number of fungal aerosol particles that can reach the depths of the lungs during the summer was 2.35 times higher than that ground raising.3.The airborne fungi and the external environment has some common dominant fungus genera,which was different by seasons.In spring and winter,the dominant fungus genera of enclosed sheep house was Penicillium spp.,and in summer,it's Alternaria spp.,In autumn,it's Cladosporium spp.The dominant fungi genera in the semi-enclosed sheep house were Cladosporium spp in summer,and the other seasonal were Penicillium spp.The distribution of the dominant fungi outside of four seasons were consistent with that from enclosed sheep house.The dominant of airborne fungus by net rearing in spring was Aspergillus spp,and the other seasonal dominant fungi genera were Penicillium spp.The dominant fungus by ground rearing in summer was Cladosporium spp,and the other seasonal dominant fungi genera were Penicillium spp.The dominant fungi genera outside in spring,summer,autumn and winter were respectively Penicillium spp.?Yeast?Mycelia Sterilia?Penicillium spp.The dominant fungus genera of feed and feces was Yeast.4.The fingerprint of ERIC-PCR showed that fungus genera of the semi-enclosed sheep house was more abundant than that of the enclosed type,and fungus genera of net rearing was more abundant than that of ground rearing.The statistics of Shannon-Wiener diversity index and Simpson dominance index results showed that the differences of airborne fungi diversity distribution in different structure and feeding way was not significant.However,in the clustering tree,most of the samples form branches through the structure and feeding mode of the sheep,and the samples of the same season form small branches.These results indicated that the distribution of mycoflora was affected by the structure and rearing patterns,and the flora changes were seasonal.5.The similarity coefficient of the semi-enclosed sheep house inner and outside was higher than that of the enclosed sheep house.The similar coefficients of airborne fungi from enclosed sheep house and semi-enclosed sheep house were higher than that of the feces fungi.The similar coefficients of airborne fungi by net rearing of airborne fungi and matrix fungi flora was higher than that by ground rearing.Similarity coefficient of net rearing of airborne fungi and feed was higher,and Similarity coefficient of ground rearing of airborne fungi and feces fungi was higher.