Table 2.

Infectious dose of in vitro-grown E. coliO157:H7 in sheep

StrainTime p.i.No. of animals positive/no. inoculated at a STEC dosea of:
105 CFUa104 CFU
86-24Initial4/62/6
2 wk2/60/6
2 mo1/60/6
3081Initial2/60/6
2 wk0/60/6
2 mo0/60/6
2041Initial6/66/6
2 wk6/63/6
2 mo2/60/6
637Initial6/64/6
2 wk2/61/6
2 mo0/60/6
E2348/69Initial6/65/6
2 wk0/63/6
2 mo0/60/6
  • a STEC 86-24 and 3081 were inoculated at 105 or 104 CFU/strain/animal, and ETEC 2041, ETEC 637, and EPEC E2348/69 were inoculated at 1010CFU/strain/animal.