Burns A L, Ball H J, Finlay D A
Department of Bacteriology, Veterinary Sciences Division, Stoney Road, Stormont, Belfast, Northern Ireland.
Vet Microbiol. 1996 Apr;49(3-4):235-41. doi: 10.1016/0378-1135(95)00196-4.
Tissue culture assays were used to investigate the incidence of cytotoxic necrotising factors (CNFs) 1 and 2 in Escherichia coli strains from cattle. E. coli cultures were obtained from faeces collected from 223 cases of diarrhoea and from 113 healthy animals. In addition, strains cultured from 62 cases of mastitis, 66 cases of septicaemia and 68 cases of abortion were also investigated. E. coli producing CNF 1 or 2 were identified in all sample groups except for the abortion cases. Comparable levels of CNF1 strains were present in E. coli from the faces of diarrhoeic (4%) and healthy faeces (4.4%) whereas lower levels of CNF2 were identified in the faeces from diarrhoeic animals (19.3%) in comparison with healthy animals (30.9%). One CNF1 producing strain was identified among the E. coli isolated from mastitis samples, while 3% and 10.6% of septicaemic strains were positive for CNF1 and 2, respectively. Serogrouping of CNF isolates did not reveal the association of any particular serogroups with the different conditions.
采用组织培养试验研究牛源大肠杆菌菌株中细胞毒性坏死因子（CNF）1和2的发生率。大肠杆菌培养物取自223例腹泻病例和113头健康动物的粪便。此外，还对从62例乳腺炎、66例败血症和68例流产病例中培养出的菌株进行了研究。除流产病例外，在所有样本组中均鉴定出产生CNF 1或2的大肠杆菌。腹泻粪便（4%）和健康粪便（4.4%）中的大肠杆菌中CNF1菌株水平相当，而腹泻动物粪便（19.3%）中CNF2水平低于健康动物（30.9%）。从乳腺炎样本中分离出的大肠杆菌中有1株产生CNF1，而败血症菌株中分别有3%和10.6%的菌株对CNF1和CNF2呈阳性。对CNF分离株进行血清分型未发现任何特定血清群与不同病症之间存在关联。
