Study On The Variance Of Antibiotic Resistance Of E Coli Of Swine Of Different Years On Phenotype And Genotype Level

Procine enteropathogenic E.coli of two different years in southwest of China were provided by Sichuan University Bioengineering Research Center for Animal Disease Prevention and Control,and procine enteropathogenic E.coli of 2006 in China were identificated the serotype,tested resistance phenotype using K-B which is recommended by CLSI and detected resistance genotype useing PCR.The prevalence of resisitance phenotype and resistant genotype of procine enteropathogenic E.coli of three different years(1999,2003 and 2006) in southwest of China were compared.It showed that the main serotype of three different years have great changes.The mian serotypes in 1999 are O9(14.3%),O60(9.5%),O89(14.3%),O101(9.5%),O119(14.3%)and O141(9.5%).The mian serotypes in 2003 are O8(8.7%),O9(8.7%),O38(8.9%),O138(13.0%),O139(8.9%),O141(8.9%)and O157(13.0%).The mian serotypes in 2006 are O8(11.8%),O20(17.6%),O45(11.8%),O60(11.8%),O101(17.6%) and O141(11.8%).It showed that,the resistances rates in southwest of China have great changese and resistance rates increased year by year.The resistance rates of 1999 are:SMZ 23.5%,SXT 19.5%,STR 20.0%,GEN 26.7%,KAN 26.7%,NEO 10.0%,SPT 20.0%,TM 6.7%,FLR 33.3%,TCY 93.3%,DOX 53.3%;The resistance rates of 2003 are:SMZ 53.3%,SXT 50.0%,STR 50.0%,GEN 33.3%,KAN 80.0%,NEO 16.7%,SPT 20.0%,TM 3.3%,FLR 56.7%,TCY 100%,DOX 83.3%;The resistance rates of 2006 are:SMZ 76.7%,SXT 80.0%,STR 90.0%,GEN 40.0%,KAN 70.0%,NEO 46.7%,SPT 20.0%,TM 26.7%,FLR 50.0%,TCY 100%,DOX 96.7%。There were changes of resistance genes in southwest of China of different years and the detection rates raise year by year.The detection rates of resistance genes of 1999 were sul1 23.3%,sul2 6.7%,sul3 3.3%,aadA1 6.7%,aaC2 3.3%,aaC4 6.7%,aph3 3.3%,Cat1 13.3%,CmlA 3.3%,floR 3.3%,tetA 16.7%,tetC 16.7%,tetM 13.3%;The detection rates of resistance genes of 2003 were sul1 46.7%,sul2 16.7%,sul3 3.3%,aadA1 36.7%,aaC2 23.3%,aaC4 16.7%,aph36.7%,Cat1 26.7%,CmlA 13.3%,floR 13.3%,tetA 23.3%,tetC 23.3%,tetM 23.3%; The detection rates of resistance genes of 2006 were sul1 73.3%,sul2 30.0%,sul3 6.7%,aadA1 76.7%,aaC2 53.3%,aaC4 20.0%,aph3 6.7%,Cat1 30.0%,CmlA 16.7%,floR 20.0%,tetA 40.0%,tetC 40.0%,tetM 23.3%。The main resistance genotype of 1999 were sul1 16.7%,aadA1 6.7%,Cat1 10.0%,tetC 10.0%和tetA6.7%;The main resistance genotype of 2003 were sul1 36.7%,sul1/sul2 10.0%,aadA1 13.3%,aaC2 6.7%,aadA1/aaC2 6.7%,aadA1/aaC4 6.7%,Cat1 16.7%,floR 6.7%,Cat1/cmlA6.7%,tetC 16.7%,tetA 10.0%,tetA/tetM 6.7%和tetC/tetM 6.7%;The main resistance genotype of 2006 were sul1 46.6%,sul1/sul2 23.3%,aadA1 26.7%,aaC2 10.0%,aadA1/aaC2 33.3%,aadA1/aaC4 6.7%,Cat1 20.0%,floR 10.0%,Cat1/cmlA 6.7%,floR/cmlA 6.7%,tetC 20.0%,tetA 10.0%,tetM 6.7%,tetA/tetM 10.0%,tetC/tetM 10.0%和tetA/tetC/tetM 6.7%。Compered resistance phenotype and resistance genotype and the results showed that the meet rates were high.This study was the first time to compare resisitace phenotype and resistance genotype of three different years in southwest of China.The prevalence of drug resistance of E.coli can provide guidance to choose effective drug and provide a scientific basis to control infection of pathogenic E.coli.