Gannon V P, Gyles C L, Friendship R W
Department of Veterinary Microbiology and Immunology, Ontario Veterinary College, University of Guelph.
Can J Vet Res. 1988 Jul;52(3):331-7.
Porcine verotoxigenic Escherichia coli were characterized with respect to frequency of occurrence, serogroup, and association with disease, weaning, and selected properties of the bacterium. Of 668 strains of E. coli from southern Ontario pigs with enteric disease, 32 (4.8%) produced verotoxin at 10(3)-10(7) cytotoxic doses per mL of culture supernatant. Of 22 isolates which belonged to O serogroups 138, 139 and 141, 15 produced verotoxin. Among other enterotoxigenic types of E. coli, two of 57 isolates of O157:K"V17" and two of 96 isolates of O149:K91 were verotoxigenic. The remaining 13 verotoxigenic E. coli belonged to O groups 2, 107, 120, 121 and 130. An additional 21 verotoxigenic E. coli belonging to O groups 138, 139 and 141 and three to O157:K"V17" were identified in a collection of 47 E. coli recovered from weaned pigs with enteric disease. Verotoxigenic E. coli were associated with postweaning diarrhea, bloody stools, sudden death and edema disease. They were isolated at similar frequencies (14%) from healthy weaned pigs, and from weaned pigs with enteric disease. Isolation rates from neonates were low and significantly different from rates in weaned pigs. Neutralizing antibody to verotoxin was not detected in the sera of 45 pigs, which included pigs from herds with a history of edema disease. Verotoxin was not associated with production of colicin, hemolysin, or enterotoxins or with any of 23 biochemical properties of the organisms. The serological data indicate that porcine verotoxigenic E. coli are not a common source of verotoxigenic E. coli for humans. Porcine verotoxin may play a role in postweaning diarrhea and absence of detectable neutralizing antibody in serum may be an important aspect of pathogenesis.
对猪产志贺毒素大肠杆菌进行了发病率、血清群以及与疾病、断奶和细菌特定特性之间关系的研究。在安大略省南部患肠道疾病的猪的668株大肠杆菌中，32株（4.8%）每毫升培养上清液产生10(3)-10(7)细胞毒素剂量的志贺毒素。在属于O血清群138、139和141的22株分离株中，15株产生志贺毒素。在其他产肠毒素类型的大肠杆菌中，57株O157:K"V17"分离株中的2株和96株O149:K91分离株中的2株产志贺毒素。其余13株产志贺毒素大肠杆菌属于O群2、107、120、121和130。在从患肠道疾病的断奶仔猪中分离出的47株大肠杆菌中，又鉴定出另外21株属于O血清群138、139和141的产志贺毒素大肠杆菌以及3株O157:K"V17"。产志贺毒素大肠杆菌与断奶后腹泻、血便、猝死和水肿病有关。它们从健康断奶仔猪和患肠道疾病的断奶仔猪中分离出来的频率相似（14%）。从新生仔猪中分离的频率较低，且与断奶仔猪的频率有显著差异。在45头猪的血清中未检测到针对志贺毒素的中和抗体，其中包括有水肿病史猪群中的猪。志贺毒素与大肠杆菌素、溶血素或肠毒素的产生无关，也与该生物体的23种生化特性中的任何一种无关。血清学数据表明，猪产志贺毒素大肠杆菌不是人类产志贺毒素大肠杆菌的常见来源。猪志贺毒素可能在断奶后腹泻中起作用，血清中未检测到中和抗体可能是发病机制的一个重要方面。
