畜牧与饲料科学2024，Vol.45Issue(4)：103-109,7.DOI:10.12160/j.issn.1672-5190.2024.04.013
额敏县1株羊粪源金黄色葡萄球菌的分离鉴定及其耐药性与致病性研究
Isolation,Identification,Antimicrobial Resistance and Pathogenicity of a Staphylococcus aureus Strain from Feces of Sheep in Emin County,China
摘要
Abstract
[Objective]The aims of the present study were to isolate and identify the Staphylococcus aureus(S.aureus)strain from fecal samples of lambs with diarrhoea,and to characterize the antimicrobial resistance and pathogenicity of the isolate.[Method]Four anal swab samples of diarrheic lambs were collected from a sheep farm in Emin County,Tacheng Prefecture,Xinjiang Uygur Autonomous Region,and S.aureus strain was selectively isolated with mannitol salt agar(MSA).The isolate was identified by morphological observation and 16S rDNA sequence analysis.The in vitro susceptibility of the isolate to 11 antimicrobial agents belonging to 9 categories was analyzed by paper diffusion method.The presence of virulence genes of the isolate was detected by PCR assay.A model of abdominal infection in Kunming mice was established to evaluate the pathogenicity of the isolate.[Result]One suspected S.aureus strain was isolated from the four fecal samples of diarrheic lambs.It formed glossy,moderately raised,golden or lemon coloured colonies on MSA.Gram staining and morphological observation revealed that the isolate was Gram-positive and arranged in the form of grape bunches.The 16S rDNA sequence of the isolate was 100%similar to that of a S.aureus isolate of porcineluny origin from Changsha City,Hunan Province,China.Morphological observation and 16S rDNA sequence analysis confirmed that the isolate was S.aureus.The isolate was resistant to penicillin,clindamycin,cefotiamine,rifampicin and erythromycin,and was sensitive to gentamicin,azithromycin,chloramphenicol,norfloxacin,cefoxitin and cotrimoxazole.Out of the 20 virulence genes belonging to 8 classes tested,the presence of sea,seg,sei,eta,clfA and clfB genes was observed.The LD50 of the isolate for Kunming mice was 2.24×108 CFU/mL,with observable pathological changes in the organs of the dead mice.[Conclusion]One S.aureus strain was isolated and identified from the fecal samples of diarrheic lambs in a sheep farm in Emin County,which exhibited a multi-drug resistant phenotype,harbored multiple virulence genes and had certain pathogenicity.The results of this study provide references for the rational use of medication for the diseases caused by S.aureus infection in sheep in this region.关键词
羊/金黄色葡萄球菌/分离/鉴定/耐药性/致病性Key words
sheep/Staphylococcus aureus/isolation/identification/antimicrobial resistance/pathogenicity分类
农业科技引用本文复制引用
苏政,于月通,朱婷婷,陀海欣,李静,吴静,刘鹏,彭健,齐萌..额敏县1株羊粪源金黄色葡萄球菌的分离鉴定及其耐药性与致病性研究[J].畜牧与饲料科学,2024,45(4):103-109,7.基金项目
新疆生产建设兵团科技创新人才计划(2021CB062) （2021CB062）
新疆生产建设兵团第九师科技计划项目(2021JS001,2022JS008). （2021JS001,2022JS008）
