TABLE 2.
Effect of vaccination of pregnant dams with intiminO157 on experimental E. coli O157:H7 infection in suckling piglets
| Vaccination and litter(s) | No. of piglets positive/no. tested
|
|||||
|---|---|---|---|---|---|---|
| Colonizeda
|
A/E lesions in large intestineb
|
|||||
| Total | 2-4 days pi | 6-10 days pi | Total | 3-4 days pi | 6-10 days pi | |
| IntiminO157 | ||||||
| A + C + E | 6/25c | 5/20 | 1/5 | 8/25c, d | 6/20d | 2/5 |
| A | 1/8 | 1/8 | NDe | 1/8d | 1/8d | ND |
| C | 5/8 | 4/6 | 1/2 | 7/8d | 5/6d | 2/2 |
| E | 0/9 | 0/6 | 0/3 | 0/9 | 0/6 | 0/3 |
| Sham (TBS) | ||||||
| B + D + F | 25/30 | 17/22 | 8/8 | 26/30 | 18/22 | 8/8 |
| B | 8/11 | 6/9 | 2/2 | 9/11 | 7/9 | 2/2 |
| D | 9/9 | 6/6 | 3/3 | 9/9 | 6/6 | 3/3 |
| F | 8/10 | 5/7 | 3/3 | 8/10 | 5/7 | 3/3 |
a
≥106 CFU of inoculum bacteria/g of cecum.
b
A/E lesions identified as O157:H7+ by immunostaining.
c
Significantly different from sham-vaccinated piglets (P < 0.05 [chi-square analysis]).
d
A/E lesions were detected only by HRPO, and not by H&E staining, in one piglet in litter A and two in litter C.
e
ND, not done.