Pollution Characteristics Of Antibiotic Resistance Genes And Distribution Of Antibiotic Resistant Bacteria In PM_2.5,Feces And Soil Of Broiler Farms

Environmental pollution from acquiring antibiotic resistance genes?ARGs?and antibiotic resistance bacteria?ARB?is largely attributed to excessive use and abuse of antibiotics,which further reduced its potential for treating multiple pathogenic bacteria in humans and animals.Livestock feces are generally considered to be important reservoirs of reservoir of antibiotics,ARB and ARGs,which are released into the environment with fecal discharge,accelerating the spread of antibiotic resistance in the environment.Intestinal bacteria in poultry is an important environmental reservoir that leads to antibiotic resistance of human pathogens.Therefore,this paper studied the ARGs abundance and diversity,bacterial community structure,and the distribution of the ARB in the PM_2.5,feces and soil samples of concentrated broiler feeding operations in Changzhou,analyzed the role of a class I integrin?int1?and bacterial community in ARGs environmental transmission,and evaluated ARGs exposure in respiratory pathways.The specific conclusions are as follows:?1?Sulfonamide resistance genes,macrolide resistance genes and tetracycline resistance genes were detected with high abundance in PM_2.5,feces and soil samples of the broiler feeding operations.In the micro-environment of broiler feeding,feces were an important source of ARGs in PM_2.5 inside broiler feeding operation.Int1 had a significant positive correlation with ARGs,which promoted the spread of ARGs in different environmental media.PM_2.5 could serve as a reservoir for multidrug resistance,with the high exposure and daily intake of int1 and ARGs.?2?The bacterial community structure and diversity of PM_2.5 and feces were relatively similar.UPGMA clustering analysis showed that feces contribute more to PM_2.5 in broiler feeding operations.Meanwhile,the relative abundance of human potential pathogens in PM_2.5 and feces was higher than that in soil.Redundancy analysis showed that the relationship between different ARGs and bacterial communities in broiler farms was similar,indicating that ARGs in different environmental media had similar fates.At the same time,dominant bacteria may play an important role in the resistance change in broiler feeding operations.The results of co-occurrence patterns analysis showed that a variety of ARGs could be carried by Staphylococcus,Bacteroides and Jeotgalicoccus,and Staphylococcus as a typical human pathogen with a greater risk.?3?The multiple drug resistance rates of soil,feces,PM_2.5 outside broiler feeding operation and PM_2.5 inside broiler feeding operation were38.46%,100%,33.33%and 100%,respectively.Bacillus thuringiensis was a multi-drug resistant pathogen in soil,while Staphylococcus sciuri,Staphylococcus lentus,Staphylococcus arlettae,Enterococcus faecalis,Enterococcus gallinarum and Streptococcus pluranimalium were multi-drug resistant pathogens in feces and PM_2.5.