Madoroba Evelyn, Van Driessche Edilbert, De Greve Henri, Mast Jan, Ncube Ignatious, Read John, Beeckmans Sonia
Department of Microbiology and Plant Pathology, University of Pretoria, 0002, Pretoria, South Africa.
Trop Anim Health Prod. 2009 Oct;41(7):1539-47. doi: 10.1007/s11250-009-9345-4. Epub 2009 Apr 4.
World-wide, enterotoxigenic Escherichia coli (ETEC) and verotoxigenic E. coli (VTEC)-induced diarrhea are economically important for porcine producers. Our aim was to investigate the prevalence of toxin and fimbrial genes among E. coli isolated from diarrheic piglets from randomly selected piggeries in Zimbabwe. We used multiplex PCR for screening STa, STb, LT, and Stx-2e toxins. Subsequently F4, F5, F6, F18 and F41 fimbriae genes were screened in toxin positive isolates. Toxin positive strains lacking tested fimbriae genes were characterized using transmission electron microscopy, agglutination and agglutination inhibition tests. Approximately 32% of the 1,984 isolates tested positive for STa, STb, LT or Stx-2e genes. Of these, approximately 81% had F4, F5, F6, F18 or F41 fimbriae genes. The remaining toxin positive strains lacked tested fimbriae genes and appeared to either express F1-like fimbriae, or lacked fimbriae. The data constitute an important framework for implementation of prevention measures, such as using relevant fimbriae-based vaccines against ETEC induced diarrhea or VTEC-induced edema.
在全球范围内，产肠毒素大肠杆菌（ETEC）和产志贺毒素大肠杆菌（VTEC）引起的腹泻对养猪生产者来说具有重要的经济意义。我们的目的是调查从津巴布韦随机选择的猪场腹泻仔猪分离出的大肠杆菌中毒素和菌毛基因的流行情况。我们使用多重PCR筛选耐热肠毒素a（STa）、耐热肠毒素b（STb）、不耐热肠毒素（LT）和志贺毒素2e（Stx-2e）毒素。随后，在毒素阳性分离株中筛选F4、F5、F6、F18和F41菌毛基因。使用透射电子显微镜、凝集和凝集抑制试验对缺乏检测菌毛基因的毒素阳性菌株进行鉴定。在检测的1984株分离株中，约32%对STa、STb、LT或Stx-2e基因呈阳性。其中，约81%具有F4、F5、F6、F18或F41菌毛基因。其余毒素阳性菌株缺乏检测的菌毛基因，似乎要么表达F1样菌毛，要么缺乏菌毛。这些数据为实施预防措施提供了重要框架，例如使用相关的基于菌毛的疫苗预防ETEC引起的腹泻或VTEC引起的水肿。
