肠炎沙门氏菌对雏鸭致病性差异与携带毒力基因相关性研究

Research on the Relationship between the Pathogenicity Variations of Salmonella Enteritidis in Ducklings and the Presence of Virulence Genes

为了探究肠炎沙门氏菌的致病性差异,选择7株鸭源肠炎沙门氏菌开展动物试验,并检测了20种毒力基因(avrA、sipA、sipC、sopA、ssaB、mgtC、misL、orf319、sopB、siiE、pipC、stn、fimA、spvB、spvD、spvC、sitC、sefA、sifA、pefA)在不同菌株中的分布情况,对毒株致病性与携带毒力基因的相关性进行分析。结果表明,所有肠炎沙门氏菌对雏鸭均有致病性,但致病性存在明显差异,致死率为12%~87.5%。毒力基因检测结果显示,不同菌株携带的毒力基因存在差异,其中SE115、SE161菌株携带基因avrA、sipA、sipC、sopA、sopB、ssaB、mgtC、misL、siiE、pipC、stn、fimA、orf319、spvB、spvC、sitC、sefA、sifA、pefA等19种毒力基因;SE60、SE62、SE63菌株除携带上述基因外,还携带spvD基因;SE39菌株携带avrA、sipA、sipC、sopA、sopB、ssaB、mgtC、misL、siiE、pipC、stn、fimA、orf319、sitC、sefA、sifA、pefAd等17种毒力基因;SE56菌株携带avrA、misL、ssaB、spvB、spvD等5种毒力基因。上述结果说明不同菌株的鸭源肠炎沙门氏菌对雏鸭的致病性存在差异,这种差异与其携带毒力基因的数量和种类有一定相关性,此研究结果为进一步研究沙门氏菌的致病机理提供基础理论。

In order to investigate the pathogenicity of duck-derived Salmonella enteritidis,in this study,animal experiments were carried out with seven strains of duck-derived S.enteritidis and the virulence genes(avrA,sipA,sipC,sopA,ssaB,mgtC,misL,orf319,sopB,siiE,pipC,stn,fimA,spvB,spvD,spvC,sitC,sefA,sifA,pefA) in different strains were detected,then the correlation between strain pathogenicity and virulence genes was analyzed.The results showed that S.enteritidis strains showed different pathogenicity to ducklings,with the lethality ranging from 12% to 87.5%.The results of virulence genes detection showed that different S.enteritidis strains carried various virulence genes.Among them,SE115 and SE161 strains both carried genes of avrA,sipA,sipC,sopA,sopB,ssaB,mgtC,misL,siiE,pipC,stn,fimA,orf319,spvB,spvC,sitC,sefA,sifA,pefA.Despite the genes above,SE60,SE62,and SE63 strains also carried spvD gene.SE39 strain carried 17 virulence genes including avrA,sipA,sipC,sopA,sopB,ssaB,mgtC,misL,siiE,pipC,stn,fimA,orf319,sitC,sefA,sifA,pefA.SE56 strain only carried 5 virulence genes,including avrA,misL,ssaB,spvB,spvD.The results of this study revealed that S.enteritidis strains exhibited different pathogenicity to ducklings,and this pathogenicity was correlated with the amount and type of virulence genes they carried.The results of the study would provide bases for further research on the pathogenic mechanism of S.enteritidis.