【摘要】 目的研制一种对猪链球菌有较强选择作用的选择性培养基,用于污染标本中分离猪链球菌。方法通过药物敏感实验筛选对猪链球菌2型不敏感的抗菌药物,继而用琼脂平板稀释法测定候选抗菌药物的MIC,组方后测定猪链球菌生长率,用模拟标本和猪源标本考核分离效果。结果研制成功含3种抗菌药物的透明指示选择性培养基(简称StS培养基),该培养基对猪链球菌2型的生长率为85.9%～94.7%,对大肠埃希菌、铜绿假单胞菌、肺炎克雷伯等常见革兰阴性细菌和革兰阳性菌中的葡萄球菌、乙型溶血性链球菌、粪链球菌抑菌率100%。当模拟杂菌为108cfu/ml时,直接涂抹法检测灵敏度为7×103cfu/ml,较使用萘啶酮酸血平板提高1000倍。通过选择肉汤增菌后,StS培养基可使猪源标本猪链球菌检出率从0提高到14.9%。结论该培养基对猪链球菌具有较强的选择作用,使用该选择性培养基可以提高检测灵敏度,适合猪链球菌的动物源性标本与传染源追踪检测。更多还原

【Abstract】 Objective To develop a selective medium that shows comparable stronger selective action to streptococcus suis in order to isolate streptococcus suis from the pollution sample.Methods Through the experiment of drug sensitivity analysis to select the antimicrobial that do not sensitive to streptococcus suis type 2,then use plate dilution method to determine the MIC of the prepared selective antimicrobial,to determine the growth rate of streptococcus suis after compounding,then use the simulation sample and source pig sample to check the isolating result.Result A transparent instructing selective medium(StS medium)which include 3 kinds of antimicrobial was developed,its growth rate to streptococcus suis type 2 was 85.9% to 94.7%,its bacteriostasis rate to staphylococci,β-hemolytic streptococci and streptococcus faecium which are in the common Gram-positive bacteria and Gram-negative bacteria such as Escherichia coli,pseudomonas aeruginosa and klebsiella pneumoniae was 100%.When the simulating mixed bacteria was 108 cfu/ml,the detect sensitivity of direct culture was 7×103 cfu/ml,1 000 times higher than when use nalidixic acid blood plate.After incubation in selective broth,StS made the positive rate of source pig sample increased from 0 to 14.9 %.Conclusion This selective medium was strongly selective to streptococcus suis,and by using it can raise the detect sensitivity which fits the animal source sample and infection source tracing detection of streptococcus suis.更多还原