| Campylobacter jejuni is one of zhe common food-borne zoonotic pathogens,and it is harmful to human health by consuming animal products containing the bacteria to induce food-borne diseases.In recent years,with the development of science and technology,a large number of antibiotics have been synthesized,and antibiotics have been used unreasonably in the process of livestock and poultry breeding.The drug resistance problem of Campylobacter jejuni has become increasingly serious.Studies have shown that the formation of bacterial biofilms plays a certain role in the pathogenic process of Campylobacter jejuni.Domestic scholars have extensively studied Campylobacter jejuni,but there is a lack of research on the prevalence,drug resistance and biofilm formation of Campylobacter jejuni from different animal sources in Xinjiang.In this study,we isolated and identified Campylobacter jejuni from cattle,sheep and chickens around Urumqi,Xinjiang,and analyzed its drug resistance and biofilm formation to provide a reference for the prevalence of Campylobacter jejuni from different animal sources in Urumqi.The results of this study are as follows:1.From 2020 to 2021,this study collected a total of 1189 samples from cattle,sheep and chicken sources in Urumqi,including 562 cattle source samples,331 sheep source samples and296 chicken source samples.Campylobacter jejuni was isolated and identified by medium culture and PCR identification,and the isolated strains were sequenced for homology analysis.The results showed that 51 strains of Campylobacter jejuni were isolated,and the total pollution rate was4.29%（51/1189）.The pollution rates of bovine,sheep and chicken samples were 3.91%（22/562）,3.02%（10/331）and 6.42%（19/296）respectively.At the same time,the homology of Campylobacter jejuni isolates from different animal sources ranged from 93.3%to 99.7%.2.In this study,51 strains of Campylobacter jejuni from different animal sources were tested for drug susceptibility of 23 antibiotics by disk diffusion method.The results showed that all strains of Campylobacter jejuni were resistant to antibiotics.Among them,ampicillin,amoxicillin,tetracycline,clindamycin and lincomycin had high drug resistance,and the drug resistance rate was 86.27%～92.16%,kanamycin,doxycycline,streptomycin,erythromycin,chloramphenicol,naphthyridic acid the drug resistance rate of cefotaxime,ceftriaxone and cotrimoxazole was60.78%-78.43%,the multi drug resistance rate was 92.16%,resulting in 45 drug resistance profiles.Cattle isolates showed high drug resistance to ampicillin（86.36%）,amoxicillin（86.36%）,clindamycin（90.91%）,the multiple drug resistance rate was 90.91%,producing 20 drug resistance profiles;Sheep isolates showed high drug resistance to ampicillin（100.00%）,amoxicillin（90.00%）,clindamycin（100.00%）,the multiple drug resistance rate reached 100.00%,resulting in10 drug resistance profiles;Chicken isolates showed high drug resistance to ampicillin（84.21%）,amoxicillin（84.21%）,clindamycin（89.47%）,the multiple drug resistance reached 94.74%,resulting in 17 drug resistance profiles.The multiple drug resistance of 51 isolates from different animal sources was concentrated in 14.In this study,51 strains of Campylobacter jejuni were detected by PCR,the detection rate of tetracycline resistance genes（tet A,tet B,tet C）was 84.31%,the detection rate of macrolide resistance genes（erm B,erm C,erm F）was 40.92%,The detection rate ofβ-lactam resistance genes(bla TEM,bla SHV-1)was 98.04%,and the detection rate of quinolone resistance related genes（gyr A,gyr B,par C）was 82.35%.All 51 Campylobacter jejuni isolates form different animal sources contained drug resistance genes.The carrying rate of bla SHV-1was the highest among the isolates from cattle,sheep and chicken,with the carrying rates of 86.36%,90.00%and 89.47%respectively;The isolates from cattle,sheep and chicken produced 20,10 and17 drug resistance genotypes respectively.3.In this study,51 isolates of Campylobacter jejuni were tested for biofilm formation and film-forming related genes.And the OD590 nmvalues of Campylobacter jejuni isolateds form different animals were measured to determine the biofilm-forming ability of Campylobacter jejuni.The results showed that the biofilm-forming ability of the isolated for 72 h was significantly higher than that cultured for 48 h at 37°C（P<0.001）,the biofilm forming ability of the isolates cultured for 48 h was significantly higher than that of the isolates cultured for 24 h（P<0.001）.The biofilm forming ability of the isolates was directly proportional to the culture time.In this study,PCR was used to detect the film-forming related genes of Campylobacter jejuni form different animal sources,The results showed that the isolates carried the film-forming-related genes fla A,fli A,Luxs,rpo N,cmec,cad F,rac R,peb1A and Peb4,and carrying rates are 0%,43.14%,39.22%,41.18%,31.37%,39.22%,29.41%,31.37%,0%,respectively.and the total carrier rate of membrane-forming-related genes was 88.24%（45/51）,resulting in a total of 37membrane-forming-related gene profiles.To sum up,the cattle,sheep and chicken industries in this region are all contaminated by Campylobacter jejuni and may spread along the production chain.The isolates from different animal sources have a wide drug resistance spectrum and have multi-drug resistance problems.Bacterial biofilm and film-forming-related genes are widely present in Campylobacter jejuni isolates,and the film-forming-related gene spectrum is complex and diverse. |
