Study On Virulence Genes,Drug Resistance And Multi-Locus Sequence Typing Of Enterococcus Faecalis Isolated From Pigs And Chickens Of Some Farms In Hunan

Enterococcus fascalis is a widely distributed opportunistic pathogen that causes a variety of diseases in humans and animals.In recent years,under the unreasonable use of antibiotics,the drug resistance of Enterococcus faecalis has become increasingly serious,combined with its numerous virulence genes and complex pathogenic mechanisms,making the clinical treatment of Enterococcus faecalis infection more difficult.Multi-site sequence typing(MLST)is a simple and high-resolution typing method.It mainly performs the typing of strains by analyzing the nucleic acid sequences of multiple housekeeping genes.It has a special MLST database,which can realize the exchange of information between strains from different countries and different regions.MLST has laid a foundation for studying the correlation between population structure,drug resistance characteristics,and epidemiology of strains from different sources.In order to understand the virulence gene carrying,the characteristics of drug resistance and the prevalence of multi-drug resistant strainsof Enterococcus faecalis in Hunan Province,the isolation and identification of Enterococcus faecalis in pigs and chickens in some areas were carried out,and the virulence genes and drug resistance of the isolates were tested.Then MLST methods were used to classify some multi-drug resistant strains in this study.It provided a basis for guiding the administration of Enterococcus faecalis infection.The results of this study are as follows: 81 strains of Enterococcus faecalis were isolated,the isolation rate of chicken source(35.8%)was higher than that of pig source(28.4%);all virulence genes were detected except esp,and more than 85% of the strains were detected Carrying two or more virulence genes.The isolates were highly resistant to erythromycin,tetracycline and cefoxitin,and were generally sensitive to vancomycin.The multi-drug resistance rate is above 90%.The more popular sequence types of Enterococcus faecalis in Hunan are ST16,ST476,ST480 and ST32.The results showed that the drug resistance of Enterococcus faecalis in pigs and chickens in Hunan Province was serious.The relationship between drug resistance and virulence genes needs to be further study.The Enterococcus faecalis in different complex clonal groups have certain specific antibiotics such as G(p<0.05).There is a significant difference in the resistance rates of Enterococcus faecalis in different complex clonal groups to certain specific antibiotics such as gentamicin.It suggested that the drug resistance characteristics of different ST-type Enterococcus faecalis have important guiding significance for the treatment of clinical infection of Enterococcus faecalis.