Isolation,identification And Drug Resistance Analysis Of Pathogenic Escherichia Coli From Some Pig And Chicken Farms In Chongqing

Escherichia coli is one of the resident bacteria in animal intestine,which is very important to animals.However,a few of them can cause animal diseases,including opportunistic pathogens and some pathogenic serotypes.Some special serotypes are even highly pathogenic.With the wide use of antibiotics,the increasing drug resistance of E.coli has become one of the hot issues in veterinary clinical research in China.In this study,clinical samples of pigs and chickens suspected to have died of E.coli in Yongchuan District,Tongnan District,Tongliang District,Jiangjin district and Beibei District of Chongqing were cultured and purified by maconkey agar plate culture medium,morphological observation and PCR identification were carried out,and the drug resistance of 33 commonly used antibiotics was detected by drug sensitivity test paper,Objective to analyze the drug resistance of isolated bacteria and evaluate the drug resistance of pathogenic Escherichia coli in different regions,so as to provide reference for clinical rational drug use.From 75 dead pigs and chickens collected from different farms,58 strains of pathogenic Escherichia coli were isolated and identified.The total isolation rate was 77.33%.26 strains(26 / 40,65.0%)were isolated from pig and 32(32 / 35,91.4%)from chicken.The results of drug sensitivity test showed that the drug resistance rate of different strains to the same drug was different,and the sensitivity of the same strain to different drugs was different.Among them,the drug resistance rate to lincomycin(98.28%),vancomycin(98.28%),tetracycline(91.38%)and other 12 drugs was high,all above 60%;all the isolates were the most sensitive to amikacin,the drug resistance rate was only 3.45%,which proved that the drug was the best in clinical use.The drug resistance rates of Pathogenic E.coli Isolated from pigs and chickens from different areas were different.The drug resistance rates of pathogenic Escherichia coli strains isolated from different areas were significantly different to the same drug;the sensitivity of different strains in the same area to different drugs was also different.Among them,the comprehensive drug resistance rate of Pathogenic E.coli Isolated from Beibei was the highest,while that in Tongnan district was lower than that in other areas;the drug resistance rate of strains isolated from different areas to penicillin,vancomycin,tetracycline,lincomycin and clindamycin was high.Therefore,it is suggested that such drugs should be avoided in veterinary clinic.The drug resistance rate of pig strains to 21,28,30 and 31 drugs was 0,and the lowest resistance was 3 kinds of drugs.The ratio of 3,4,5 and 6 drug resistance was 0.The lowest multi drug resistance was 7 kinds of drug resistance,and the most resistant was 31 kinds of drugs.The multi drug resistance of pathogenic Escherichia coli strains from chicken was higher than that of pig strains.