四川省山羊源沙门菌血清型鉴定及毒力基因的分布

Distribution of Serovars and Virulence Genes in SalmonellaIsolates from Goats in Sichuan Province

调查四川省山羊源沙门菌血清型及部分毒力基因的分布及其致病性,为食品安全控制提供参考。采用沙门菌单因子血清对42株山羊源沙门菌血清型进行鉴定,并用PCR检测其携带invA、sopE、orgA、avrA、ttrB、sseL、rhuM、mgtC、orfL、sopB、pipD、sodC1、lpfC、pefA、spvC等15个毒力基因的情况;根据血清型和毒力基因的携带情况选取山羊源沙门菌菌株,采用灌胃法对BALB/c小鼠进行攻毒试验。血清学鉴定结果显示,23株为布利丹沙门菌、15株为肠炎沙门菌、3株为阿贡纳沙门菌、1株为纽波特沙门菌;PCR检测结果显示,42株沙门菌均携带invA、orgA、pipD、sopB、lpfC5种毒力基因,sopE、sseL、ttrB、rhuM、sodC1、pefA、spvC、avrA、mgtC、orfL的携带率分别为97.6%、97.6%、88.1%、95.2%、92.9%、47.6%、47.6%、40.5%、40.5%、38.1%;每个菌株携带6~15种毒力基因,且发现有2株阿贡纳沙门菌携带毒力质粒;携带15个毒力基因的2株布利丹沙门菌、2株肠炎沙门菌和2株阿贡纳沙门菌均在5×108 CFU剂量下致死全部未经抗生素处理的小鼠,其中肠炎沙门菌SWUN3816对小鼠的LD50为1.6×102 CFU。综上可见,布利丹沙门菌和肠炎沙门菌是四川省山羊源沙门菌的优势血清型,首次发现阿贡纳沙门菌携带毒力质粒。

The aim of this study was to investigate the serovars and virulence genes as well as the pathogenicity of Salmonella isolates from goats in Sichuan Province, which will provide the information for food safety. The 42 Salmonella strains from goats were identified by the mono-specific serum, and the carrying rates of 15 virulence genes, including invA, sopE, orgA, avrA, ttrB, sseL, rhuM, mgtC, orfL,sopB, pipD,sodC1, lpfC, pefA and spvC, were detected by PCR. According to the results of serovars and virulence genes, 6 of the Salmonella strains were select- ed and studied the pathogenicity in BALB/c mice by oral infection. The serotyping results exhibi- ted that the 42 Salmonella isolates were divide into 4 different serovars, incuding S. Blegdam （23/42）, S. Enterica （15/42）, S. Agona （3/42） and S. Newport （1/42）. In 42 Salmonella strains, all isolates carried the five virulence genes of invA, orgA, pipD, sopB and lpfC. The carrying rates of the virulence genes of sopE, sseL, ttrB, rhuM, sodC1, pefA, spvC, avrA, mgtC and orfL were 97. 6%, 97. 6%, 88. 1%, 95. 2%, 92. 9%, 47. 6%, 47. 6%, 40. 5%,40.5% and 38.1%, respectively. Each strain carried at least 6 virulence genes, and two S. Ago- na strains carried virulence plasmid. There were two of S. enteritidis strains, two of S. Blegdam strains and two of S. Agona strains carrying 15 virulence genes, which could killed the no-antibi- otics treated mice at the doses of 5×10^8 CFU. Furthermore, the LDs0 of the S. enteritidis strain SWUN3816 was 1.6×10^2 CFU to mice. Both S. Blegdarn and S. Enterica were dominant serovars from goats in Sichuan Province, and it was first to identify the S. Agona strain carrying virulence plasmid.