摘要
对中国内蒙古自治区饲育马土壤环境中马红球菌的分布知之甚少;为此,在中国内蒙古通辽近郊、内蒙古南部锡林郭勒盟大草原、内蒙古东部呼伦贝尔大草原等马场共收集了108份土壤样品进行了马红球菌的检测。结果,锡林郭勒盟大草原和呼伦贝尔大草原的马红球菌分离率为25.9%～30.0%,通辽近郊土壤中分离率高达82.3%。这说明在通辽近郊马红球菌的分离菌数是草原土壤中马红球菌分离菌数的10倍。应用PCR技术检测了488株的毒力相关基因,相对分子质量分别为15000～17000(VapA)和20000(VapB)。所有的分离株都未检出毒力相关基因。这些无毒力分离株的质粒资料显示,各种大小的潜在质粒的发生率为13.3%～21.5%。本研究结果截然不同于我们新近对蒙古国的调查结论:马红球菌在蒙古国乌兰巴托的马群中不存在。造成这一差异的原因可能在于蒙古国的游牧生活和内蒙古的非游牧生活。
Little is known about the distribution of Rhodococcus equi in the soil environment of native horses in China. One hundred and eight soil samples were collected from native-horso farms in the Hulun Beier grasslands of eastern Mongolia, the Xilin Goler grasslands of southern Mongolia, and Tongliao city in Inner Mongolia of China for investing the distribution of R. equi in these regions.The isolation rates of R. equi from soil samples from the Hulun Beier and Xilin Goler grasslands ranged from 25.9% to 30.0%. In contrast,isolation rates from soil samples from Tonghao city was as high as 82.3% and the mean number of R. equi in soil samples from Tongliao city was 10 times more than those of samples from the grasslands. The 488 isolates were examined using PCR for the presence of genes that encode virulence-associated 15 000-17 000 antigen protein （VapA） and the 20 000 antigen protein （VapB）. All isolates were negative for virulence-associated proteins. Plasmid profiles of these avirulent isolates showed that cryptic plasmids of various sizes were present with an incidence of 13.3% to 21.5%. The results of the present study contrast with those of our recent study, in which we reported that R. equi was absent from Mongolian homes in Ulaanbaatar, Mongolia. It is suggested that the difference between the results of these two studies is due to the mobile pasturing system in Mongolia and nonmo-bile pasturing system in Inner Mongolia.
出处
《中国兽医学报》
CAS
CSCD
北大核心
2008年第1期40-44,共5页
Chinese Journal of Veterinary Science
基金
This study was supported by a grant-in-aidfor general scientific research(Takai:14405031,16380208)
关键词
马红球菌
内蒙古
饲育马
土壤
Rhodococcus equi
Inner Mongolia
native horse
soil
