Epidemiological distribution characteristics and transmission patterns of Campylobacter in a Shandong broiler slaughterhouse
10.3969/j.issn.1002-2694.2025.00.102
- VernacularTitle:山东某大型肉鸡屠宰场弯曲菌分布特征及传播规律研究
- Author:
Shuai MIAO
1
;
Xiu-mei HUANG
;
Lin WANG
;
Jun-hui LIU
;
Jian-mei ZHAO
;
Yu-bin GAO
;
Shi-ping SONG
;
Si-yu ZHANG
;
Na LIU
;
Ge ZHAO
;
Xi-yue ZHANG
;
Jun-wei WANG
;
Juan WANG
;
Zhi-na QU
Author Information
1. 中国动物卫生与流行病中心,青岛 266032;东北农业大学动物医学学院,哈尔滨 150006
- Publication Type:Journal Article
- Keywords:
Campylobacter;
drug resistance;
whole genome sequencing(WGS);
molecular epidemiology
- From:
Chinese Journal of Zoonoses
2025;41(6):583-591
- CountryChina
- Language:Chinese
-
Abstract:
This research investigated the contamination level,distribution of drug-resistant strains,and molecular epidemiologi-cal characteristics of Campylobacter,and further explored transmission pathways and prevention strategies.Cecum,chicken carcass,chicken product,and environmental samples,as well as swabs from workers'hands,were collected from a slaughterhouse in a large broiler group in the Jiaodong area between August 2023 and July 2024.Quantitative contamination assessment of Campylobacter in chicken carcasses and chicken products was performed.After microbial mass spectrometry identification,the representative strains of different links were selected for drug resistance testing and whole genome sequencing(WGS).On the basis of the sequencing results,the resistance genes,virulence genes,multilocus sequence typing(MLST),and phylogenetic characteristics of representative strains were analyzed.Homology comparisons were performed between isolates and strains from patients with diarrhea in the NCBI database.A total of 297 Campylobacter strains were isolated from 806 samples,and the overall detection rate was 36.85%.The detection rate of Campylobacter was highest in the evisceration process(47.33%),followed by the cutting process(35.64%).Overall,the Campylo-bacter detection rate first increased,then decreased,and subsequently increased.Drug sensitivity testing revealed that 90 isolates were resistant to nalidixic acid and ciprofloxacin,and 94.97%of isolates were resistant to tetracycline.WGS showed that both Campylo-bacter jejuni(C.jejuni)and Campylobacter coli(C.coli)carried many drug resistance and virulence genes.ST-14176 of C.jejuni was isolated for the first time herein.The predominant ST-8261 strain of C.jejuni and ST-860,ST-829,and ST-1586 strains of C.coli are known to cause human diarrhea.LOS expression genes associated with Guillain-Barré syndrome(GBS)were detected in both C.jejuni isolates from the slaughter chain and patients with GBS.Some strains exhibited close genetic relatedness to human-derived Campylo-bacter strains from the NCBI database.The detection rate of Campylobacter in the slaughterhouse first increased,then decreased,and subsequently increased,and the quantitative contamination level of each link was similar to the detection rate.Quantitative analysis of chicken carcasses/products revealed that the average bacterial load was highest in eviscerated carcasses(102.80 cfu/g),and the high-est amount of Campylobacter in chicken products reached 451.80 cfu/g.Abundant drug resistance genes and virulence genes were iden-tified,and the drug resistance genes were highly correlated with the drug resistance rate.Therefore,surveillance intensity and control measures for Campylobacter in slaughter processes should be strengthened.
