Moon H W, Schneider R A, Moseley S L
Am J Vet Res. 1986 Feb;47(2):210-2.
Presence of Escherichia coli enterotoxin genes LT (heat-labile enterotoxin), STaP (heat-stable enterotoxin a, porcine genotype), STaH (heat-stable enterotoxin a, human genotype), and STb (heat-stable enterotoxin b) among 874 swine isolates of E coli was determined, using DNA probes and the DNA colony hybridization technique. Of the 874 isolates evaluated, 45% hybridized with at least one of the enterotoxin gene probes and were designated as enterotoxigenic E coli (ETEC). Eighty-five percent of the ETEC were from pigs with enteric colibacillosis. The remaining 15% were from pigs with edema disease or various other diseases, and from healthy swine. Seventy-four percent of the ETEC hybridized with the STb probe, 52% with STaP, and 31% with LT; ETEC did not hybridize with the STaH probe. Most of the ETEC hybridized with more than one enterotoxin gene probe. Isolates that hybridized with the LT probe also hybridized with STb. The most prevalent gene combination was LT-STb. However, 35% of the ETEC from neonatal (less than or equal to 1 week old) swine with enteric colibacillosis were of the STaP-only genotype, and 33% of the ETEC from older swine with enteric colibacillosis were of the STb-only genotype.
利用DNA探针和DNA菌落杂交技术，对874株猪源大肠杆菌分离株中是否存在大肠杆菌肠毒素基因LT（热不稳定肠毒素）、STaP（热稳定肠毒素a，猪基因型）、STaH（热稳定肠毒素a，人基因型）和STb（热稳定肠毒素b）进行了测定。在评估的874株分离株中，45%与至少一种肠毒素基因探针杂交，被指定为产肠毒素大肠杆菌（ETEC）。85%的ETEC来自患有肠道大肠杆菌病的猪。其余15%来自患有水肿病或其他各种疾病的猪以及健康猪。74%的ETEC与STb探针杂交，52%与STaP杂交，31%与LT杂交；ETEC未与STaH探针杂交。大多数ETEC与不止一种肠毒素基因探针杂交。与LT探针杂交的分离株也与STb杂交。最常见的基因组合是LT-STb。然而，患有肠道大肠杆菌病的新生仔猪（小于或等于1周龄）中35%的ETEC仅为STaP基因型，患有肠道大肠杆菌病的大龄猪中33%的ETEC仅为STb基因型。
