福建地区副猪嗜血杆菌的主要生物学特性

Main biological characterization of Haemophilus parasuis derived from Fujian Province

为明确福建地区副猪嗜血杆菌的耐药性、血清型及其外膜蛋白P5(OmpP5)的同源性,对来自福建地区的患病猪进行了副猪嗜血杆菌的分离与鉴定,并采用琼脂扩散试验对其进行血清型鉴定和药敏试验;选取10株不同血清型代表株进行致病性试验;测定5株不同血清型菌株的OmpP5基因序列,比较相互间的同源性及与其他生物学特性的关系。结果显示,分离株的生化特性基本一致,代表株对小鼠有一定的致病性;所有分离菌株具有一种以上的耐药性,100%的菌株对青霉素、氨苄青霉素、新霉素和洁霉素敏感,93%和87%的菌株分别对链霉素和杆菌肽耐药;分离获得的52株菌株分属于5种血清型,其中24株为血清13型,12株为血清4型,11株为血清5型,2株为血清2型,3株未定型;5株代表菌株中OmpP5基因序列的同源性在93%以上,氨基酸序列同源性在91%以上。研究表明,该外膜蛋白P5基因与菌株的血清型和菌株的致病性无直接关系。

To make clear the resistance,serotype and OmpP5 homology of Haemophilus parasuis from Fujian Province,52 strains of H.parasuis were isolated and identified from diseased pigs derived from Fujian Province.The serotypes were classified by the agar diffusion test,and drug sensitivity of the strains was determined by the K-B test.The pathogenicity of 10 type strains of the H.parasuis to BALB/c mouse was tested,and OmpP5 gene homology of 5 strains of H.parasuis belonging to different serotypes was blasted.The results showed that all the isolates had similar biochemical characteristics,and were resistant at less to one antibiotic,the presentative strains had limited pathogenicity to BALB/c mouse;100% of the isolates were sensitive to penicillin,ampicillin,neomycin and lincomycin;93% and 87% of the isolates were respectively resistant to streptomycin and bacitracin.All the isolates were classified into 5 serotypes,i.e.24,12,11,2 and 3 isolates were regarded as serotypes 13,4,5,2 and non-serotype respectively.The gene and amino acid homologies of OmpP5 were up to 93% and 91% respectively.The present study suggested that OmpP5 gene was not closely related with serotype and pathogenicity of H.parasuis.