Contamination Status Of Avian-Derived Salmonella In Some Areas Of Shandong And Isolation And Identification Drug Resistance Analysis

Salmonella is widely present in the gastrointestinal tract and daily environment of humans and animals,is a common conditional pathogenic bacteria,with the abuse of antibiotics,has developed different degrees of resistance to commonly used antibacterial drugs,not only restricting the development of poultry industry,but also seriously threatening human public health security.Studies have shown that the clinical detection rate and drug resistance rate of Salmonella have been increasing year after year,and the high resistance rate of this bacterium has made it a reservoir of drug resistance genes,which constitutes a key link in the horizontal transmission of drug resistance genes.Therefore,this study deeply understood the prevalence of Salmonella in the environment of meat duck and broiler farms in some areas of Shandong Province,isolated and cultured and identified Salmonella by molecular biology and other methods,and analyzed the serotype,drug resistance phenotype and drug resistance gene distribution of 187 isolated strains of Salmonella.To clarify the epidemic characteristics and transmission rules of meat and poultry farming,and explore the source of Salmonella infection.In order to understand and mitigate the impact of antibioticresistant bacteria on poultry farming,and standardize the clinical selection of antibiotics,this paper provides theoretical basis and data support.Through sample collection of meat duck and broiler farm environment,manure and cloaca in some areas of Shandong,the detection rate of salmonella in meat and duck farm samples was 17.11%.Among them,the strains detected from meat and duck farms from high to low were: feces(40 plants),> duck cloaca(21 plants),> feeding trough(14 plants),> wall,floor(11 plants),> cages(9 plants),> sinks(4 plants).The bacterial detection rate of broiler farm samples was 12.90%.The strains detected by Salmonella in broiler farms in descending order were: feces(27 strains),> ground(26 strains),> chicken cloaca(20 strains),> sink,feeding trough(2 strains).The results showed that the detection rates of four different serotypes of Salmonella were: Salmonella albicana 18.18%(34/187),>Salmonella enteritidis13.37%(25/187),Salmonella enteritidis 13.37%(25/187),> Salmonella typhimurium 12.83%(24/187)> Salmonella typhi 10.16%(19/187).187 strains of Salmonella poultry were tested for resistance rates in 11 commonly used antibiotics(florfenicol,amoxicillin,neomycin sulfate,colistin sulfate,apramycin sulfate,ceftiofur sodium,telmicosin,enrofloxacin,daguanlincomycin,doxycycline,ampicillin)in187 strains of Salmonella avia.The results showed that the highest resistance rate of Salmonella avian to florfenicol,amoxicillin and ampicillin was 100%,and the resistance rate to ceftiofur sodium was 91.44%.The resistance rate of telmicocin was 99.64%,respectively;The resistance rates of neomycin sulfate and apramycin sulfate were 95.18% and 89.83%,respectively.The resistance rate to daigulincomycin was 98.39%;The resistance rate of enrofloxacin was 92.51%;The resistance rate of doxycycline was 90.37%,and colistin sulfate was the lowest,with a resistance rate of 67.91%.The multidrug resistance rate in this trial was100%.The strains with resistance 11 accounted for 60.43%(113/187),followed by 22.99%(43/187)and 12.30%(23/187)with 12.30%(23/187).The 8-,7-and 6-resistant strains accounted for 3.21%,0.53% and 0.53%,respectively.The detection of 187 strains of Salmonella from different sources using PCR technology showed that flo R had the highest detection rate of drug-resistant genes,accounting for97.86%;The detection rates of other resistance genes were sul2(97.33%)> sul1(95.19%)>aac(6’)-Ib(91.98%)> tet C(81.82%)> bla CTX-M(80.75%)> ere A(75.40%)> bla TEM(56.68%),aac(3)-II.(44.39%)> oqx A(37.97%)> oqx B(32.62%)> mcr1(28.88%)> bla CIT(24.60%)> erm B(12.30%)> mcr3(6.42%)> Lnu(C)(3.74%);The tet M resistance gene was not detected.A variety of resistance genes were detected at the same time,from high to low: 9(18.72%)> 8(16.58%)> 7(14.44%)> 11(13.90%)> 10(9.09%)> 12(8.56%)> 6(6.95%)> 5(4.28%)> 13(3.21%)> 4(3.20%)> 1(1.6%).In summary,through the isolation and identification of Salmonella and the phenotype of drug resistance in broiler duck and broiler farms in some areas of Shandong,the prevalence of Salmonella poultry in this region was investigated,and the background of Salmonella resistance was clarified.By further testing the resistance genes carried by Salmonella isolates from poultry,the mechanism of drug resistance of isolated bacteria was preliminarily revealed,which provided new ideas for solving the increasingly serious problem of Salmonella resistance in commercial meat duck farms and broiler farms.